diff --git a/.eslintrc.json b/.eslintrc.json
index e263c13450..392804daad 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -348,6 +348,7 @@
         {
             "files": ["frontend_tests/**"],
             "globals": {
+                "CSS": false,
                 "document": false,
                 "navigator": false,
                 "window": false
diff --git a/frontend_tests/node_tests/activity.js b/frontend_tests/node_tests/activity.js
index 9becf0a9ae..a4936847b5 100644
--- a/frontend_tests/node_tests/activity.js
+++ b/frontend_tests/node_tests/activity.js
@@ -286,7 +286,7 @@ function buddy_list_add(user_id, stub) {
         stub.attr("data-user-id", user_id);
     }
     stub.length = 1;
-    const sel = `li.user_sidebar_entry[data-user-id='${user_id}']`;
+    const sel = `li.user_sidebar_entry[data-user-id='${CSS.escape(user_id)}']`;
     $("#user_presences").set_find_results(sel, stub);
 }
 
diff --git a/frontend_tests/node_tests/billing_helpers.js b/frontend_tests/node_tests/billing_helpers.js
index 59e17dc961..e2c644260d 100644
--- a/frontend_tests/node_tests/billing_helpers.js
+++ b/frontend_tests/node_tests/billing_helpers.js
@@ -254,12 +254,12 @@ run_test("set_tab", () => {
         scrollTop: 0,
     };
 
-    $('#upgrade-tabs.nav a[href="#billing"]').tab = (action) => {
+    $('#upgrade-tabs.nav a[href="\\#billing"]').tab = (action) => {
         state.show_tab_billing += 1;
         assert.equal(action, "show");
     };
 
-    $('#upgrade-tabs.nav a[href="#payment-method"]').tab = (action) => {
+    $('#upgrade-tabs.nav a[href="\\#payment-method"]').tab = (action) => {
         state.show_tab_payment_method += 1;
         assert.equal(action, "show");
     };
diff --git a/frontend_tests/node_tests/dropdown_list_widget.js b/frontend_tests/node_tests/dropdown_list_widget.js
index 5d5601301b..680b61a652 100644
--- a/frontend_tests/node_tests/dropdown_list_widget.js
+++ b/frontend_tests/node_tests/dropdown_list_widget.js
@@ -21,8 +21,8 @@ const setup_zjquery_data = (name) => {
     const input_group = $(".input_group");
     const reset_button = $(".dropdown_list_reset_button");
     input_group.set_find_results(".dropdown_list_reset_button:enabled", reset_button);
-    $(`#${name}_widget #${name}_name`).closest = () => input_group;
-    const $widget = $(`#${name}_widget #${name}_name`);
+    $(`#${CSS.escape(name)}_widget #${CSS.escape(name)}_name`).closest = () => input_group;
+    const $widget = $(`#${CSS.escape(name)}_widget #${CSS.escape(name)}_name`);
     return {reset_button, $widget};
 };
 
diff --git a/frontend_tests/node_tests/reactions.js b/frontend_tests/node_tests/reactions.js
index 08204ce424..9809fda2cd 100644
--- a/frontend_tests/node_tests/reactions.js
+++ b/frontend_tests/node_tests/reactions.js
@@ -349,7 +349,7 @@ run_test("get_reaction_section", () => {
     const message_row = $.create("some-message-row");
     const message_reactions = $.create("our-reactions-section");
 
-    message_table.set_find_results("[zid='555']", message_row);
+    message_table.set_find_results(`[zid='${CSS.escape(555)}']`, message_row);
     message_row.set_find_results(".message_reactions", message_reactions);
 
     const section = reactions.get_reaction_section(555);
@@ -439,7 +439,7 @@ run_test("add_and_remove_reaction", () => {
     reaction_element.set_find_results(".message_reaction_count", count_element);
 
     message_reactions.find = function (selector) {
-        assert.equal(selector, "[data-reaction-id='unicode_emoji,1f3b1']");
+        assert.equal(selector, "[data-reaction-id='unicode_emoji\\,1f3b1']");
         return reaction_element;
     };
 
@@ -506,7 +506,7 @@ run_test("add_and_remove_reaction", () => {
     };
 
     message_reactions.find = function (selector) {
-        assert.equal(selector, "[data-reaction-id='realm_emoji,991']");
+        assert.equal(selector, "[data-reaction-id='realm_emoji\\,991']");
         return reaction_element;
     };
     reaction_element.prop = function () {};
diff --git a/frontend_tests/node_tests/settings_org.js b/frontend_tests/node_tests/settings_org.js
index eacfddc248..051f2525c6 100644
--- a/frontend_tests/node_tests/settings_org.js
+++ b/frontend_tests/node_tests/settings_org.js
@@ -154,10 +154,10 @@ function test_realms_domain_modal(add_realm_domain) {
 }
 
 function createSaveButtons(subsection) {
-    const stub_save_button_header = $(`#org-${subsection}`);
+    const stub_save_button_header = $(`#org-${CSS.escape(subsection)}`);
     const save_button_controls = $(".save-button-controls");
-    const stub_save_button = $(`#org-submit-${subsection}`);
-    const stub_discard_button = $(`#org-discard-${subsection}`);
+    const stub_save_button = $(`#org-submit-${CSS.escape(subsection)}`);
+    const stub_discard_button = $(`#org-discard-${CSS.escape(subsection)}`);
     const stub_save_button_text = $(".save-discard-widget-button-text");
     stub_save_button_header.set_find_results(
         ".subsection-failed-status p",
@@ -169,7 +169,7 @@ function createSaveButtons(subsection) {
     stub_save_button_header.set_find_results(".save-button-controls", save_button_controls);
     stub_save_button_header.set_find_results(
         ".subsection-changes-discard .button",
-        $(`#org-discard-${subsection}`),
+        $(`#org-discard-${CSS.escape(subsection)}`),
     );
     save_button_controls.set_find_results(".discard-button", stub_discard_button);
     const props = {};
@@ -222,7 +222,7 @@ function test_submit_settings_form(submit_form) {
     };
 
     let subsection = "other-permissions";
-    ev.currentTarget = `#org-submit-${subsection}`;
+    ev.currentTarget = `#org-submit-${CSS.escape(subsection)}`;
     let stubs = createSaveButtons(subsection);
     let save_button = stubs.save_button;
     save_button.attr("id", `org-submit-${subsection}`);
@@ -253,7 +253,7 @@ function test_submit_settings_form(submit_form) {
     email_address_visibility_elem.attr("id", "id_realm_email_address_visibility");
     email_address_visibility_elem.data = () => "number";
 
-    let subsection_elem = $(`#org-${subsection}`);
+    let subsection_elem = $(`#org-${CSS.escape(subsection)}`);
     subsection_elem.closest = () => subsection_elem;
     subsection_elem.set_find_results(".prop-element", [
         bot_creation_policy_elem,
@@ -277,7 +277,7 @@ function test_submit_settings_form(submit_form) {
     assert.deepEqual(data, expected_value);
 
     subsection = "user-defaults";
-    ev.currentTarget = `#org-submit-${subsection}`;
+    ev.currentTarget = `#org-submit-${CSS.escape(subsection)}`;
     stubs = createSaveButtons(subsection);
     save_button = stubs.save_button;
     save_button.attr("id", `org-submit-${subsection}`);
@@ -291,7 +291,7 @@ function test_submit_settings_form(submit_form) {
     realm_default_twenty_four_hour_time_elem.attr("id", "id_realm_default_twenty_four_hour_time");
     realm_default_twenty_four_hour_time_elem.data = () => "boolean";
 
-    subsection_elem = $(`#org-${subsection}`);
+    subsection_elem = $(`#org-${CSS.escape(subsection)}`);
     subsection_elem.closest = () => subsection_elem;
     subsection_elem.set_find_results(".prop-element", [
         realm_default_language_elem,
@@ -1017,7 +1017,7 @@ run_test("misc", () => {
         $.create("<disable button>"),
     );
     for (const name of widget_settings) {
-        const elem = $.create(`#${name}_widget #${name}_name`);
+        const elem = $.create(`#${CSS.escape(name)}_widget #${CSS.escape(name)}_name`);
         elem.closest = () => dropdown_list_parent;
     }
 
@@ -1030,7 +1030,7 @@ run_test("misc", () => {
     settings_org.init_dropdown_widgets();
 
     let setting_name = "realm_notifications_stream_id";
-    let elem = $(`#${setting_name}_widget #${setting_name}_name`);
+    let elem = $(`#${CSS.escape(setting_name)}_widget #${CSS.escape(setting_name)}_name`);
     elem.closest = function () {
         return stub_notification_disable_parent;
     };
@@ -1047,7 +1047,7 @@ run_test("misc", () => {
     assert(elem.hasClass("text-warning"));
 
     setting_name = "realm_signup_notifications_stream_id";
-    elem = $(`#${setting_name}_widget #${setting_name}_name`);
+    elem = $(`#${CSS.escape(setting_name)}_widget #${CSS.escape(setting_name)}_name`);
     elem.closest = function () {
         return stub_notification_disable_parent;
     };
diff --git a/frontend_tests/node_tests/settings_user_groups.js b/frontend_tests/node_tests/settings_user_groups.js
index 47b25736a0..17db804d95 100644
--- a/frontend_tests/node_tests/settings_user_groups.js
+++ b/frontend_tests/node_tests/settings_user_groups.js
@@ -90,12 +90,12 @@ run_test("can_edit", () => {
     assert(settings_user_groups.can_edit(1));
 });
 
-const user_group_selector = "#user-groups #1";
-const cancel_selector = "#user-groups #1 .save-status.btn-danger";
-const saved_selector = "#user-groups #1 .save-status.sea-green";
-const name_selector = "#user-groups #1 .name";
-const description_selector = "#user-groups #1 .description";
-const instructions_selector = "#user-groups #1 .save-instructions";
+const user_group_selector = `#user-groups #${CSS.escape(1)}`;
+const cancel_selector = `#user-groups #${CSS.escape(1)} .save-status.btn-danger`;
+const saved_selector = `#user-groups #${CSS.escape(1)} .save-status.sea-green`;
+const name_selector = `#user-groups #${CSS.escape(1)} .name`;
+const description_selector = `#user-groups #${CSS.escape(1)} .description`;
+const instructions_selector = `#user-groups #${CSS.escape(1)} .save-instructions`;
 
 run_test("populate_user_groups", () => {
     const realm_user_group = {
@@ -169,7 +169,7 @@ run_test("populate_user_groups", () => {
 
     const all_pills = new Map();
 
-    const pill_container_stub = $('.pill-container[data-group-pills="1"]');
+    const pill_container_stub = $(`.pill-container[data-group-pills="${CSS.escape(1)}"]`);
     pills.appendValidatedData = function (item) {
         const id = item.user_id;
         assert(!all_pills.has(id));
@@ -397,7 +397,7 @@ run_test("with_external_user", () => {
     set_global("$", make_zjquery());
 
     let user_group_find_called = 0;
-    const user_group_stub = $('div.user-group[id="1"]');
+    const user_group_stub = $(`div.user-group[id="${CSS.escape(1)}"]`);
     const name_field_stub = $.create("fake-name-field");
     const description_field_stub = $.create("fake-description-field");
     const input_stub = $.create("fake-input");
@@ -413,7 +413,7 @@ run_test("with_external_user", () => {
         throw new Error(`Unknown element ${elem}`);
     };
 
-    const pill_container_stub = $('.pill-container[data-group-pills="1"]');
+    const pill_container_stub = $(`.pill-container[data-group-pills="${CSS.escape(1)}"]`);
     const pill_stub = $.create("fake-pill");
     let pill_container_find_called = 0;
     pill_container_stub.find = function (elem) {
diff --git a/frontend_tests/node_tests/stream_edit.js b/frontend_tests/node_tests/stream_edit.js
index ddfc0cba37..bf6119c341 100644
--- a/frontend_tests/node_tests/stream_edit.js
+++ b/frontend_tests/node_tests/stream_edit.js
@@ -98,8 +98,9 @@ for (const sub of subs) {
 const subscriptions_table_selector = "#subscriptions_table";
 const input_field_stub = $.create(".input");
 
-const sub_settings_selector =
-    "#subscription_overlay .subscription_settings[data-stream-id='" + denmark.stream_id + "']";
+const sub_settings_selector = `#subscription_overlay .subscription_settings[data-stream-id='${CSS.escape(
+    denmark.stream_id,
+)}']`;
 const $sub_settings_container = $.create(sub_settings_selector);
 $sub_settings_container.find = noop;
 $sub_settings_container.find = function () {
diff --git a/frontend_tests/node_tests/stream_events.js b/frontend_tests/node_tests/stream_events.js
index 3d9eebac3a..cd028d3a22 100644
--- a/frontend_tests/node_tests/stream_events.js
+++ b/frontend_tests/node_tests/stream_events.js
@@ -95,7 +95,7 @@ run_test("update_property", (override) => {
     }
 
     function checkbox_for(property) {
-        return $(`#${property}_${stream_id}`);
+        return $(`#${CSS.escape(property)}_${CSS.escape(stream_id)}`);
     }
 
     // Test desktop notifications
diff --git a/frontend_tests/node_tests/subs.js b/frontend_tests/node_tests/subs.js
index 8f34d950b7..0185078146 100644
--- a/frontend_tests/node_tests/subs.js
+++ b/frontend_tests/node_tests/subs.js
@@ -111,7 +111,7 @@ run_test("filter_table", () => {
     const sub_stubs = [];
 
     for (const data of populated_subs) {
-        const sub_row = ".stream-row-" + data.elem;
+        const sub_row = `.stream-row-${CSS.escape(data.elem)}`;
         sub_stubs.push(sub_row);
 
         $(sub_row).attr("data-stream-id", data.stream_id);
@@ -149,7 +149,7 @@ run_test("filter_table", () => {
 
     // Filtering has the side effect of setting the "active" class
     // on our current stream, even if it doesn't match the filter.
-    const denmark_row = $(`.stream-row[data-stream-id='${denmark_stream_id}']`);
+    const denmark_row = $(`.stream-row[data-stream-id='${CSS.escape(denmark_stream_id)}']`);
     // sanity check it's not set to active
     assert(!denmark_row.hasClass("active"));
 
diff --git a/frontend_tests/node_tests/upload.js b/frontend_tests/node_tests/upload.js
index c227bc9005..23a8a1c2d3 100644
--- a/frontend_tests/node_tests/upload.js
+++ b/frontend_tests/node_tests/upload.js
@@ -62,9 +62,12 @@ run_test("get_item", () => {
         $("#undo_markdown_preview"),
     );
 
-    assert.equal(upload.get_item("textarea", {mode: "edit", row: 1}), $("#message_edit_content_1"));
+    assert.equal(
+        upload.get_item("textarea", {mode: "edit", row: 1}),
+        $(`#message_edit_content_${CSS.escape(1)}`),
+    );
 
-    $("#message_edit_content_2").closest = () => {
+    $(`#message_edit_content_${CSS.escape(2)}`).closest = () => {
         $("#message_edit_form").set_find_results(".message_edit_save", $(".message_edit_save"));
         return $("#message_edit_form");
     };
@@ -72,14 +75,14 @@ run_test("get_item", () => {
 
     assert.equal(
         upload.get_item("send_status_identifier", {mode: "edit", row: 11}),
-        "#message-edit-send-status-11",
+        `#message-edit-send-status-${CSS.escape(11)}`,
     );
     assert.equal(
         upload.get_item("send_status", {mode: "edit", row: 75}),
-        $("#message-edit-send-status-75"),
+        $(`#message-edit-send-status-${CSS.escape(75)}`),
     );
 
-    $("#message-edit-send-status-2").set_find_results(
+    $(`#message-edit-send-status-${CSS.escape(2)}`).set_find_results(
         ".send-status-close",
         $(".send-status-close"),
     );
@@ -88,12 +91,15 @@ run_test("get_item", () => {
         $(".send-status-close"),
     );
 
-    $("#message-edit-send-status-22").set_find_results(".error-msg", $(".error-msg"));
+    $(`#message-edit-send-status-${CSS.escape(22)}`).set_find_results(
+        ".error-msg",
+        $(".error-msg"),
+    );
     assert.equal(upload.get_item("send_status_message", {mode: "edit", row: 22}), $(".error-msg"));
 
     assert.equal(
         upload.get_item("file_input_identifier", {mode: "edit", row: 123}),
-        "#message_edit_file_input_123",
+        `#message_edit_file_input_${CSS.escape(123)}`,
     );
     assert.equal(upload.get_item("source", {mode: "edit", row: 123}), "message-edit-file-input");
     assert.equal(
@@ -102,7 +108,7 @@ run_test("get_item", () => {
     );
     assert.equal(
         upload.get_item("markdown_preview_hide_button", {mode: "edit", row: 65}),
-        $("#undo_markdown_preview_65"),
+        $(`#undo_markdown_preview_${CSS.escape(65)}`),
     );
 
     assert.throws(
diff --git a/frontend_tests/puppeteer_lib/common.js b/frontend_tests/puppeteer_lib/common.js
index c680286060..8eba08788f 100644
--- a/frontend_tests/puppeteer_lib/common.js
+++ b/frontend_tests/puppeteer_lib/common.js
@@ -3,6 +3,7 @@
 const {strict: assert} = require("assert");
 const path = require("path");
 
+require("css.escape");
 const puppeteer = require("puppeteer");
 
 const {test_credentials} = require("../../var/puppeteer/test_credentials");
@@ -381,7 +382,7 @@ class CommonUtils {
      */
     async get_rendered_messages(page, table = "zhome") {
         return await page.evaluate((table) => {
-            const $recipient_rows = $(`#${table}`).find(".recipient_row");
+            const $recipient_rows = $(`#${CSS.escape(table)}`).find(".recipient_row");
             return $recipient_rows.toArray().map((element) => {
                 const $el = $(element);
                 const stream_name = $el.find(".stream_label").text().trim();
@@ -410,7 +411,7 @@ class CommonUtils {
     // The method will only check that all the messages in the
     // messages array passed exist in the order they are passed.
     async check_messages_sent(page, table, messages) {
-        await page.waitForSelector("#" + table, {visible: true});
+        await page.waitForSelector(`#${CSS.escape(table)}`, {visible: true});
         const rendered_messages = await this.get_rendered_messages(page, table);
 
         // We only check the last n messages because if we run
@@ -452,7 +453,7 @@ class CommonUtils {
 
                 const tah = $(field_selector).data().typeahead;
                 tah.mouseenter({
-                    currentTarget: $('.typeahead:visible li:contains("' + item + '")')[0],
+                    currentTarget: $(`.typeahead:visible li:contains("${CSS.escape(item)}")`)[0],
                 });
                 tah.select();
             },
diff --git a/frontend_tests/puppeteer_tests/02-message-basics.js b/frontend_tests/puppeteer_tests/02-message-basics.js
index c456aa7376..789b9ba0bd 100644
--- a/frontend_tests/puppeteer_tests/02-message-basics.js
+++ b/frontend_tests/puppeteer_tests/02-message-basics.js
@@ -6,7 +6,7 @@ const common = require("../puppeteer_lib/common");
 
 async function get_stream_li(page, stream_name) {
     const stream_id = await common.get_stream_id(page, stream_name);
-    return `#stream_filters [data-stream-id="${stream_id}"]`;
+    return `#stream_filters [data-stream-id="${CSS.escape(stream_id)}"]`;
 }
 
 async function expect_home(page) {
@@ -343,19 +343,24 @@ async function test_stream_search_filters_stream_list(page) {
 async function test_users_search(page) {
     console.log("Search users using right sidebar");
     async function assert_in_list(page, name) {
-        await page.waitForSelector(`#user_presences li [data-name="${name}"]`, {visible: true});
+        await page.waitForSelector(`#user_presences li [data-name="${CSS.escape(name)}"]`, {
+            visible: true,
+        });
     }
 
     async function assert_selected(page, name) {
-        await page.waitForSelector(`#user_presences li.highlighted_user [data-name="${name}"]`, {
-            visible: true,
-        });
+        await page.waitForSelector(
+            `#user_presences li.highlighted_user [data-name="${CSS.escape(name)}"]`,
+            {
+                visible: true,
+            },
+        );
     }
 
     async function assert_not_selected(page, name) {
         await common.assert_selector_doesnt_exist(
             page,
-            `#user_presences li.highlighted_user [data-name="${name}"]`,
+            `#user_presences li.highlighted_user [data-name="${CSS.escape(name)}"]`,
         );
     }
 
diff --git a/frontend_tests/puppeteer_tests/03-compose.js b/frontend_tests/puppeteer_tests/03-compose.js
index f98726f6d5..1fee3504cd 100644
--- a/frontend_tests/puppeteer_tests/03-compose.js
+++ b/frontend_tests/puppeteer_tests/03-compose.js
@@ -132,7 +132,7 @@ async function test_narrow_to_private_messages_with_cordelia(page) {
 async function test_send_multirecipient_pm_from_cordelia_pm_narrow(page) {
     const recipients = ["cordelia@zulip.com", "othello@zulip.com"];
     const multiple_recipients_pm = "A huddle to check spaces";
-    const pm_selector = `.messagebox:contains('${multiple_recipients_pm}')`;
+    const pm_selector = `.messagebox:contains('${CSS.escape(multiple_recipients_pm)}')`;
     await common.send_message(page, "private", {
         recipient: recipients.join(", "),
         outside_view: true,
diff --git a/frontend_tests/puppeteer_tests/04-subscriptions.js b/frontend_tests/puppeteer_tests/04-subscriptions.js
index ade26b39a9..18d94b21bd 100644
--- a/frontend_tests/puppeteer_tests/04-subscriptions.js
+++ b/frontend_tests/puppeteer_tests/04-subscriptions.js
@@ -6,7 +6,7 @@ const common = require("../puppeteer_lib/common");
 
 async function user_checkbox(page, name) {
     const user_id = await common.get_user_id_from_name(page, name);
-    return `#user-checkboxes [data-user-id="${user_id}"]`;
+    return `#user-checkboxes [data-user-id="${CSS.escape(user_id)}"]`;
 }
 
 async function user_span(page, name) {
@@ -15,7 +15,7 @@ async function user_span(page, name) {
 
 async function stream_checkbox(page, stream_name) {
     const stream_id = await common.get_stream_id(page, stream_name);
-    return `#stream-checkboxes [data-stream-id="${stream_id}"]`;
+    return `#stream-checkboxes [data-stream-id="${CSS.escape(stream_id)}"]`;
 }
 
 async function stream_span(page, stream_name) {
diff --git a/frontend_tests/puppeteer_tests/05-stars.js b/frontend_tests/puppeteer_tests/05-stars.js
index e1b873bac5..3ff498e6f5 100644
--- a/frontend_tests/puppeteer_tests/05-stars.js
+++ b/frontend_tests/puppeteer_tests/05-stars.js
@@ -12,7 +12,7 @@ async function stars_count(page) {
 
 async function toggle_test_star_message(page) {
     await page.evaluate((message) => {
-        const msg = $(`.message_content:contains(${message}):visible`).last();
+        const msg = $(`.message_content:contains("${CSS.escape(message)}"):visible`).last();
         if (msg.length !== 1) {
             throw new Error("cannot find test star message");
         }
diff --git a/frontend_tests/puppeteer_tests/07-navigation.js b/frontend_tests/puppeteer_tests/07-navigation.js
index 339af97146..cad967a15b 100644
--- a/frontend_tests/puppeteer_tests/07-navigation.js
+++ b/frontend_tests/puppeteer_tests/07-navigation.js
@@ -5,13 +5,13 @@ const {strict: assert} = require("assert");
 const common = require("../puppeteer_lib/common");
 
 async function wait_for_tab(page, tab) {
-    const tab_slector = `#${tab}.tab-pane.active`;
+    const tab_slector = `#${CSS.escape(tab)}.tab-pane.active`;
     await page.waitForSelector(tab_slector, {visible: true});
 }
 
 async function navigate_to(page, click_target, tab) {
     console.log("Visiting #" + click_target);
-    await page.click(`a[href='#${click_target}']`);
+    await page.click(`a[href='#${CSS.escape(click_target)}']`);
 
     await wait_for_tab(page, tab);
 }
diff --git a/frontend_tests/puppeteer_tests/08-admin.js b/frontend_tests/puppeteer_tests/08-admin.js
index 0a615cb9b4..188e953b3c 100644
--- a/frontend_tests/puppeteer_tests/08-admin.js
+++ b/frontend_tests/puppeteer_tests/08-admin.js
@@ -247,7 +247,7 @@ async function select_from_suggestions(page, item) {
     await page.evaluate((item) => {
         const tah = $(".create_default_stream").data().typeahead;
         tah.mouseenter({
-            currentTarget: $('.typeahead:visible li:contains("' + item + '")')[0],
+            currentTarget: $(`.typeahead:visible li:contains("${CSS.escape(item)}")`)[0],
         });
         tah.select();
     }, item);
@@ -278,7 +278,7 @@ async function test_default_streams(page) {
 
     const stream_name = "Scotland";
     const stream_id = await common.get_stream_id(page, stream_name);
-    const row = `.default_stream_row[data-stream-id='${stream_id}']`;
+    const row = `.default_stream_row[data-stream-id='${CSS.escape(stream_id)}']`;
 
     await test_add_default_stream(page, stream_name, row);
     await test_remove_default_stream(page, row);
diff --git a/frontend_tests/puppeteer_tests/11-user-deactivation.js b/frontend_tests/puppeteer_tests/11-user-deactivation.js
index 6155657bff..3504a064a5 100644
--- a/frontend_tests/puppeteer_tests/11-user-deactivation.js
+++ b/frontend_tests/puppeteer_tests/11-user-deactivation.js
@@ -15,7 +15,7 @@ async function navigate_to_user_list(page) {
 
 async function user_row(page, name) {
     const user_id = await common.get_user_id_from_name(page, name);
-    return `.user_row[data-user-id="${user_id}"]`;
+    return `.user_row[data-user-id="${CSS.escape(user_id)}"]`;
 }
 
 async function test_deactivate_user(page) {
diff --git a/frontend_tests/puppeteer_tests/14-copy-and-paste.js b/frontend_tests/puppeteer_tests/14-copy-and-paste.js
index 1134c0be11..511ed550b5 100644
--- a/frontend_tests/puppeteer_tests/14-copy-and-paste.js
+++ b/frontend_tests/puppeteer_tests/14-copy-and-paste.js
@@ -8,7 +8,7 @@ async function copy_messages(page, start_message, end_message) {
     return await page.evaluate(
         (start_message, end_message) => {
             function get_message_node(message) {
-                return $('.message_row .message_content:contains("' + message + '")').get(0);
+                return $(`.message_row .message_content:contains("${CSS.escape(message)}")`).get(0);
             }
 
             // select messages from start_message to end_message
diff --git a/frontend_tests/puppeteer_tests/16-settings.js b/frontend_tests/puppeteer_tests/16-settings.js
index e5f0979695..f0406c7f6b 100644
--- a/frontend_tests/puppeteer_tests/16-settings.js
+++ b/frontend_tests/puppeteer_tests/16-settings.js
@@ -96,7 +96,9 @@ async function test_webhook_bot_creation(page) {
     await page.click("#create_bot_button");
 
     const bot_email = "1-bot@zulip.testserver";
-    const download_zuliprc_selector = '.download_bot_zuliprc[data-email="' + bot_email + '"]';
+    const download_zuliprc_selector = `.download_bot_zuliprc[data-email="${CSS.escape(
+        bot_email,
+    )}"]`;
     const outgoing_webhook_zuliprc_regex = /^data:application\/octet-stream;charset=utf-8,\[api]\nemail=.+\nkey=.+\nsite=.+\ntoken=.+\n$/;
 
     await page.waitForSelector(download_zuliprc_selector, {visible: true});
@@ -122,7 +124,9 @@ async function test_normal_bot_creation(page) {
     await page.click("#create_bot_button");
 
     const bot_email = "2-bot@zulip.testserver";
-    const download_zuliprc_selector = '.download_bot_zuliprc[data-email="' + bot_email + '"]';
+    const download_zuliprc_selector = `.download_bot_zuliprc[data-email="${CSS.escape(
+        bot_email,
+    )}"]`;
 
     await page.waitForSelector(download_zuliprc_selector, {visible: true});
     await page.click(download_zuliprc_selector);
@@ -143,10 +147,10 @@ async function test_botserverrc(page) {
 
 async function test_edit_bot_form(page) {
     const bot1_email = "1-bot@zulip.testserver";
-    const bot1_edit_btn = '.open_edit_bot_form[data-email="' + bot1_email + '"]';
+    const bot1_edit_btn = `.open_edit_bot_form[data-email="${CSS.escape(bot1_email)}"]`;
     await page.click(bot1_edit_btn);
 
-    const edit_form_selector = '.edit_bot_form[data-email="' + bot1_email + '"]';
+    const edit_form_selector = `.edit_bot_form[data-email="${CSS.escape(bot1_email)}"]`;
     await page.waitForSelector(edit_form_selector, {visible: true});
     const name_field_selector = edit_form_selector + " [name=bot_name]";
     assert(common.get_text_from_selector(page, name_field_selector), "Bot 1");
@@ -183,7 +187,7 @@ async function add_alert_word(page, word) {
 }
 
 async function check_alert_word_added(page, word) {
-    const added_alert_word_selector = `.alert-word-item[data-word='${word}']`;
+    const added_alert_word_selector = `.alert-word-item[data-word='${CSS.escape(word)}']`;
     await page.waitForSelector(added_alert_word_selector, {visible: true});
 }
 
@@ -213,7 +217,7 @@ async function test_duplicate_alert_words_cannot_be_added(page, duplicate_word)
 }
 
 async function delete_alert_word(page, word) {
-    const delete_btn_selector = `.remove-alert-word[data-word="${word}"]`;
+    const delete_btn_selector = `.remove-alert-word[data-word="${CSS.escape(word)}"]`;
     await page.click(delete_btn_selector);
     await common.assert_selector_doesnt_exist(page, delete_btn_selector);
 }
@@ -239,7 +243,7 @@ async function change_language(page, language_data_code) {
     await page.waitForSelector("#default_language", {visible: true});
     await page.click("#default_language");
     await page.waitForSelector("#default_language_modal", {visible: true});
-    const language_selector = `a[data-code="${language_data_code}"]`;
+    const language_selector = `a[data-code="${CSS.escape(language_data_code)}"]`;
     await page.click(language_selector);
 }
 
diff --git a/frontend_tests/zjsunit/index.js b/frontend_tests/zjsunit/index.js
index 12dcdb1f05..2c840d0718 100644
--- a/frontend_tests/zjsunit/index.js
+++ b/frontend_tests/zjsunit/index.js
@@ -3,6 +3,7 @@
 const Module = require("module");
 const path = require("path");
 
+require("css.escape");
 const Handlebars = require("handlebars/runtime");
 const _ = require("lodash");
 
diff --git a/frontend_tests/zjsunit/zjquery.js b/frontend_tests/zjsunit/zjquery.js
index cf4ce0e8bc..b45f3f493d 100644
--- a/frontend_tests/zjsunit/zjquery.js
+++ b/frontend_tests/zjsunit/zjquery.js
@@ -535,9 +535,6 @@ exports.make_zjquery = function (opts) {
     zjquery.clear_all_elements = function () {
         elems.clear();
     };
-    zjquery.escapeSelector = function (s) {
-        return s;
-    };
 
     return zjquery;
 };
diff --git a/package.json b/package.json
index eda6cf80ec..5ab27a9eea 100644
--- a/package.json
+++ b/package.json
@@ -23,6 +23,7 @@
     "clipboard": "^2.0.4",
     "core-js": "^3.6.5",
     "css-loader": "^5.0.0",
+    "css.escape": "^1.5.1",
     "emoji-datasource-google": "^6.0.0",
     "emoji-datasource-google-blob": "npm:emoji-datasource-google@^3.0.0",
     "emoji-datasource-twitter": "^6.0.0",
diff --git a/static/js/billing/helpers.js b/static/js/billing/helpers.js
index 06e63a873c..81372d6d44 100644
--- a/static/js/billing/helpers.js
+++ b/static/js/billing/helpers.js
@@ -7,12 +7,12 @@ exports.create_ajax_request = function (
     numeric_inputs = [],
     redirect_to = "/billing",
 ) {
-    const form = $("#" + form_name + "-form");
-    const form_loading_indicator = "#" + form_name + "_loading_indicator";
-    const form_input_section = "#" + form_name + "-input-section";
-    const form_success = "#" + form_name + "-success";
-    const form_error = "#" + form_name + "-error";
-    const form_loading = "#" + form_name + "-loading";
+    const form = $(`#${CSS.escape(form_name)}-form`);
+    const form_loading_indicator = `#${CSS.escape(form_name)}_loading_indicator`;
+    const form_input_section = `#${CSS.escape(form_name)}-input-section`;
+    const form_success = `#${CSS.escape(form_name)}-success`;
+    const form_error = `#${CSS.escape(form_name)}-error`;
+    const form_loading = `#${CSS.escape(form_name)}-loading`;
 
     const zulip_limited_section = "#zulip-limited-section";
     const free_trial_alert_message = "#free-trial-alert-message";
@@ -103,27 +103,27 @@ exports.show_license_section = function (license) {
     $("#automatic_license_count").prop("disabled", true);
     $("#manual_license_count").prop("disabled", true);
 
-    const section_id = "#license-" + license + "-section";
+    const section_id = `#license-${CSS.escape(license)}-section`;
     $(section_id).show();
-    const input_id = "#" + license + "_license_count";
+    const input_id = `#${CSS.escape(license)}_license_count`;
     $(input_id).prop("disabled", false);
 };
 
 let current_page;
 
 function handle_hashchange() {
-    $("#" + current_page + '-tabs.nav a[href="' + location.hash + '"]').tab("show");
+    $(`#${CSS.escape(current_page)}-tabs.nav a[href="${CSS.escape(location.hash)}"]`).tab("show");
     $("html").scrollTop(0);
 }
 
 exports.set_tab = function (page) {
     const hash = location.hash;
     if (hash) {
-        $("#" + page + '-tabs.nav a[href="' + hash + '"]').tab("show");
+        $(`#${CSS.escape(page)}-tabs.nav a[href="${CSS.escape(hash)}"]`).tab("show");
         $("html").scrollTop(0);
     }
 
-    $("#" + page + "-tabs.nav-tabs a").on("click", function () {
+    $(`#${CSS.escape(page)}-tabs.nav-tabs a`).on("click", function () {
         location.hash = this.hash;
     });
 
diff --git a/static/js/billing/upgrade.js b/static/js/billing/upgrade.js
index 9bd127bdd1..f185351561 100644
--- a/static/js/billing/upgrade.js
+++ b/static/js/billing/upgrade.js
@@ -16,7 +16,9 @@ exports.initialize = () => {
 
     $("#add-card-button").on("click", (e) => {
         const license_management = $("input[type=radio][name=license_management]:checked").val();
-        if (helpers.is_valid_input($("#" + license_management + "_license_count")) === false) {
+        if (
+            helpers.is_valid_input($(`#${CSS.escape(license_management)}_license_count`)) === false
+        ) {
             return;
         }
         add_card_handler.open({
diff --git a/static/js/buddy_list.js b/static/js/buddy_list.js
index 5900293af5..66427de46a 100644
--- a/static/js/buddy_list.js
+++ b/static/js/buddy_list.js
@@ -23,7 +23,7 @@ class BuddyListConf {
     get_li_from_key(opts) {
         const user_id = opts.key;
         const container = $(this.container_sel);
-        return container.find(this.item_sel + "[data-user-id='" + user_id + "']");
+        return container.find(`${this.item_sel}[data-user-id='${CSS.escape(user_id)}']`);
     }
 
     get_key_from_li(opts) {
diff --git a/static/js/bundles/common.js b/static/js/bundles/common.js
index f78f9d0e29..1209829185 100644
--- a/static/js/bundles/common.js
+++ b/static/js/bundles/common.js
@@ -1,5 +1,6 @@
 import "core-js/features/promise";
 import "core-js/features/symbol";
+import "css.escape";
 import "../../../tools/debug-require";
 import "jquery";
 import "../page_params";
diff --git a/static/js/click_handlers.js b/static/js/click_handlers.js
index c571b70bfa..36b9b6f94c 100644
--- a/static/js/click_handlers.js
+++ b/static/js/click_handlers.js
@@ -340,14 +340,14 @@ exports.initialize = function () {
     });
     $("#message_edit_form .send-status-close").on("click", function () {
         const row_id = rows.id($(this).closest(".message_row"));
-        const send_status = $("#message-edit-send-status-" + row_id);
+        const send_status = $(`#message-edit-send-status-${CSS.escape(row_id)}`);
         $(send_status).stop(true).fadeOut(200);
     });
     $("body").on("click", "#message_edit_form [id^='attach_files_']", function (e) {
         e.preventDefault();
 
         const row_id = rows.id($(this).closest(".message_row"));
-        $("#message_edit_file_input_" + row_id).trigger("click");
+        $(`#message_edit_file_input_${CSS.escape(row_id)}`).trigger("click");
     });
 
     $("body").on("click", "#message_edit_form [id^='markdown_preview_']", function (e) {
@@ -355,7 +355,7 @@ exports.initialize = function () {
 
         const row_id = rows.id($(this).closest(".message_row"));
         function $_(selector) {
-            return $(selector + "_" + row_id);
+            return $(`${selector}_${CSS.escape(row_id)}`);
         }
 
         const content = $_("#message_edit_content").val();
@@ -376,7 +376,7 @@ exports.initialize = function () {
 
         const row_id = rows.id($(this).closest(".message_row"));
         function $_(selector) {
-            return $(selector + "_" + row_id);
+            return $(`${selector}_${CSS.escape(row_id)}`);
         }
 
         $_("#message_edit_content").show();
@@ -829,12 +829,12 @@ exports.initialize = function () {
             const edit_area = $(this).parent().find(`${selector}`);
             $(selector).removeClass("stream-name-edit-box");
             if (edit_area.attr("contenteditable") === "true") {
-                $("[data-finish-editing='" + selector + "']").hide();
+                $(`[data-finish-editing='${CSS.escape(selector)}']`).hide();
                 edit_area.attr("contenteditable", false);
                 edit_area.text(edit_area.attr("data-prev-text"));
                 $(this).html("");
             } else {
-                $("[data-finish-editing='" + selector + "']").show();
+                $(`[data-finish-editing='${CSS.escape(selector)}']`).show();
 
                 $(selector).addClass("stream-name-edit-box");
                 edit_area
@@ -858,7 +858,7 @@ exports.initialize = function () {
                 map[selector].on_save(e);
                 $(this).hide();
                 $(this).parent().find(`${selector}`).attr("contenteditable", false);
-                $("[data-make-editable='" + selector + "']").html("");
+                $(`[data-make-editable='${CSS.escape(selector)}']`).html("");
             }
         });
     })();
@@ -880,7 +880,7 @@ exports.initialize = function () {
 
         overlays.open_overlay({
             name: overlay_name,
-            overlay: $("#" + overlay_name),
+            overlay: $(`#${CSS.escape(overlay_name)}`),
             on_close: function () {
                 // close popover
                 $(this).css({display: "block"});
@@ -910,7 +910,7 @@ exports.initialize = function () {
         hotspots.post_hotspot_as_read(hotspot_name);
 
         overlays.close_overlay(overlay_name);
-        $("#hotspot_" + hotspot_name + "_icon").remove();
+        $(`#hotspot_${CSS.escape(hotspot_name)}_icon`).remove();
     });
 
     $("body").on("click", ".hotspot-button", (e) => {
diff --git a/static/js/compose.js b/static/js/compose.js
index 5a3d25b6dd..5b025205fa 100644
--- a/static/js/compose.js
+++ b/static/js/compose.js
@@ -1191,7 +1191,7 @@ exports.initialize = function () {
         // compose box.
         const edit_message_id = $(e.target).attr("data-message-id");
         if (edit_message_id !== undefined) {
-            target_textarea = $("#message_edit_content_" + edit_message_id);
+            target_textarea = $(`#message_edit_content_${CSS.escape(edit_message_id)}`);
         }
 
         let video_call_link;
diff --git a/static/js/compose_state.js b/static/js/compose_state.js
index 3483efae47..39a60b6b01 100644
--- a/static/js/compose_state.js
+++ b/static/js/compose_state.js
@@ -29,7 +29,7 @@ function get_or_set(fieldname, keep_leading_whitespace) {
     // because the DOM element might not exist yet when get_or_set
     // is called.
     return function (newval) {
-        const elem = $("#" + fieldname);
+        const elem = $(`#${CSS.escape(fieldname)}`);
         const oldval = elem.val();
         if (newval !== undefined) {
             elem.val(newval);
diff --git a/static/js/composebox_typeahead.js b/static/js/composebox_typeahead.js
index 6d9e7f5c41..74b6ef364b 100644
--- a/static/js/composebox_typeahead.js
+++ b/static/js/composebox_typeahead.js
@@ -178,7 +178,7 @@ function handle_keydown(e) {
         let target_sel;
 
         if (e.target.id) {
-            target_sel = "#" + e.target.id;
+            target_sel = `#${CSS.escape(e.target.id)}`;
         }
 
         const on_stream = target_sel === "#stream_message_recipient_stream";
diff --git a/static/js/dropdown_list_widget.js b/static/js/dropdown_list_widget.js
index 107ce8cb5d..758ce79224 100644
--- a/static/js/dropdown_list_widget.js
+++ b/static/js/dropdown_list_widget.js
@@ -21,9 +21,9 @@ const DropdownListWidget = function (opts) {
     init();
 
     const render = (value) => {
-        $(`#${opts.container_id} #${opts.value_id}`).data("value", value);
+        $(`#${CSS.escape(opts.container_id)} #${CSS.escape(opts.value_id)}`).data("value", value);
 
-        const elem = $(`#${opts.container_id} #${opts.widget_name}_name`);
+        const elem = $(`#${CSS.escape(opts.container_id)} #${CSS.escape(opts.widget_name)}_name`);
 
         if (!value || value === opts.null_value) {
             elem.text(opts.default_text);
@@ -46,11 +46,11 @@ const DropdownListWidget = function (opts) {
     };
 
     const register_event_handlers = () => {
-        $(`#${opts.container_id} .dropdown-list-body`).on(
+        $(`#${CSS.escape(opts.container_id)} .dropdown-list-body`).on(
             "click keypress",
             ".list_item",
             function (e) {
-                const setting_elem = $(this).closest(`.${opts.widget_name}_setting`);
+                const setting_elem = $(this).closest(`.${CSS.escape(opts.widget_name)}_setting`);
                 if (e.type === "keypress") {
                     if (e.which === 13) {
                         setting_elem.find(".dropdown-menu").dropdown("toggle");
@@ -62,7 +62,7 @@ const DropdownListWidget = function (opts) {
                 update(value);
             },
         );
-        $(`#${opts.container_id} .dropdown_list_reset_button`).on("click", (e) => {
+        $(`#${CSS.escape(opts.container_id)} .dropdown_list_reset_button`).on("click", (e) => {
             update(opts.null_value);
             e.preventDefault();
         });
@@ -70,12 +70,16 @@ const DropdownListWidget = function (opts) {
 
     const setup = () => {
         // populate the dropdown
-        const dropdown_list_body = $(`#${opts.container_id} .dropdown-list-body`).expectOne();
-        const search_input = $(`#${opts.container_id} .dropdown-search > input[type=text]`);
-        const dropdown_toggle = $(`#${opts.container_id} .dropdown-toggle`);
+        const dropdown_list_body = $(
+            `#${CSS.escape(opts.container_id)} .dropdown-list-body`,
+        ).expectOne();
+        const search_input = $(
+            `#${CSS.escape(opts.container_id)} .dropdown-search > input[type=text]`,
+        );
+        const dropdown_toggle = $(`#${CSS.escape(opts.container_id)} .dropdown-toggle`);
 
         ListWidget.create(dropdown_list_body, opts.data, {
-            name: `${opts.widget_name}_list`,
+            name: `${CSS.escape(opts.widget_name)}_list`,
             modifier(item) {
                 return render_dropdown_list({item});
             },
@@ -85,9 +89,9 @@ const DropdownListWidget = function (opts) {
                     return item.name.toLowerCase().includes(value);
                 },
             },
-            simplebar_container: $(`#${opts.container_id} .dropdown-list-wrapper`),
+            simplebar_container: $(`#${CSS.escape(opts.container_id)} .dropdown-list-wrapper`),
         });
-        $(`#${opts.container_id} .dropdown-search`).on("click", (e) => {
+        $(`#${CSS.escape(opts.container_id)} .dropdown-search`).on("click", (e) => {
             e.stopPropagation();
         });
 
@@ -119,7 +123,9 @@ const DropdownListWidget = function (opts) {
     };
 
     const value = () => {
-        let val = $(`#${opts.container_id} #${opts.value_id}`).data("value");
+        let val = $(`#${CSS.escape(opts.container_id)} #${CSS.escape(opts.value_id)}`).data(
+            "value",
+        );
         if (val === null) {
             val = "";
         }
diff --git a/static/js/echo.js b/static/js/echo.js
index 2d970fcaba..79b4abc87b 100644
--- a/static/js/echo.js
+++ b/static/js/echo.js
@@ -367,8 +367,8 @@ function abort_message(message) {
 }
 
 exports.initialize = function () {
-    function on_failed_action(action, callback) {
-        $("#main_div").on("click", "." + action + "-failed-message", function (e) {
+    function on_failed_action(selector, callback) {
+        $("#main_div").on("click", selector, function (e) {
             e.stopPropagation();
             popovers.hide_all();
             const row = $(this).closest(".message_row");
@@ -387,8 +387,8 @@ exports.initialize = function () {
         });
     }
 
-    on_failed_action("remove", abort_message);
-    on_failed_action("refresh", resend_message);
+    on_failed_action(".remove-failed-message", abort_message);
+    on_failed_action(".refresh-failed-message", resend_message);
 };
 
 window.echo = exports;
diff --git a/static/js/emoji_picker.js b/static/js/emoji_picker.js
index 215a791661..97518403ac 100644
--- a/static/js/emoji_picker.js
+++ b/static/js/emoji_picker.js
@@ -194,7 +194,7 @@ function get_selected_emoji() {
 
 function get_rendered_emoji(section, index) {
     const emoji_id = get_emoji_id(section, index);
-    const emoji = $(".emoji-popover-emoji[data-emoji-id='" + emoji_id + "']");
+    const emoji = $(`.emoji-popover-emoji[data-emoji-id='${CSS.escape(emoji_id)}']`);
     if (emoji.length > 0) {
         return emoji;
     }
@@ -562,7 +562,9 @@ exports.emoji_select_tab = function (elt) {
     }
     if (currently_selected) {
         $(".emoji-popover-tab-item.active").removeClass("active");
-        $('.emoji-popover-tab-item[data-tab-name="' + currently_selected + '"]').addClass("active");
+        $(`.emoji-popover-tab-item[data-tab-name="${CSS.escape(currently_selected)}"]`).addClass(
+            "active",
+        );
     }
 };
 
@@ -674,7 +676,7 @@ exports.register_click_handlers = function () {
         // The following check will return false if emoji was not selected in
         // message edit form.
         if (edit_message_id !== null) {
-            const edit_message_textarea = $("#message_edit_content_" + edit_message_id);
+            const edit_message_textarea = $(`#message_edit_content_${CSS.escape(edit_message_id)}`);
             // Assign null to edit_message_id so that the selection of emoji in new
             // message composition form works correctly.
             edit_message_id = null;
diff --git a/static/js/hotspots.js b/static/js/hotspots.js
index 92c5901d95..ad248cae50 100644
--- a/static/js/hotspots.js
+++ b/static/js/hotspots.js
@@ -75,7 +75,7 @@ exports.post_hotspot_as_read = function (hotspot_name) {
 
 function place_icon(hotspot) {
     const element = $(hotspot.location.element);
-    const icon = $("#hotspot_" + hotspot.name + "_icon");
+    const icon = $(`#hotspot_${CSS.escape(hotspot.name)}_icon`);
 
     if (
         element.length === 0 ||
@@ -106,9 +106,11 @@ function place_popover(hotspot) {
         return;
     }
 
-    const popover_width = $("#hotspot_" + hotspot.name + "_overlay .hotspot-popover").outerWidth();
+    const popover_width = $(
+        `#hotspot_${CSS.escape(hotspot.name)}_overlay .hotspot-popover`,
+    ).outerWidth();
     const popover_height = $(
-        "#hotspot_" + hotspot.name + "_overlay .hotspot-popover",
+        `#hotspot_${CSS.escape(hotspot.name)}_overlay .hotspot-popover`,
     ).outerHeight();
     const el_width = $(hotspot.location.element).outerWidth();
     const el_height = $(hotspot.location.element).outerHeight();
@@ -181,7 +183,7 @@ function place_popover(hotspot) {
 
     // position arrow
     arrow_placement = "arrow-" + arrow_placement;
-    $("#hotspot_" + hotspot.name + "_overlay .hotspot-popover")
+    $(`#hotspot_${CSS.escape(hotspot.name)}_overlay .hotspot-popover`)
         .removeClass("arrow-top arrow-left arrow-bottom arrow-right")
         .addClass(arrow_placement);
 
@@ -202,7 +204,7 @@ function place_popover(hotspot) {
         };
     }
 
-    $("#hotspot_" + hotspot.name + "_overlay .hotspot-popover").css(popover_placement);
+    $(`#hotspot_${CSS.escape(hotspot.name)}_overlay .hotspot-popover`).css(popover_placement);
 }
 
 function insert_hotspot_into_DOM(hotspot) {
@@ -272,7 +274,7 @@ function close_read_hotspots(new_hotspots) {
     );
 
     for (const hotspot_name of unwanted_hotspots) {
-        exports.close_hotspot_icon($("#hotspot_" + hotspot_name + "_icon"));
+        exports.close_hotspot_icon($(`#hotspot_${CSS.escape(hotspot_name)}_icon`));
     }
 }
 
diff --git a/static/js/info_overlay.js b/static/js/info_overlay.js
index 8f47f080da..7c797d102e 100644
--- a/static/js/info_overlay.js
+++ b/static/js/info_overlay.js
@@ -15,8 +15,8 @@ exports.set_up_toggler = function () {
         ],
         callback(name, key) {
             $(".overlay-modal").hide();
-            $("#" + key).show();
-            ui.get_scroll_element($("#" + key).find(".modal-body")).trigger("focus");
+            $(`#${CSS.escape(key)}`).show();
+            ui.get_scroll_element($(`#${CSS.escape(key)}`).find(".modal-body")).trigger("focus");
         },
     };
 
@@ -26,7 +26,7 @@ exports.set_up_toggler = function () {
 
     const modals = opts.values.map((item) => {
         const key = item.key; // e.g. message-formatting
-        const modal = $("#" + key).find(".modal-body");
+        const modal = $(`#${CSS.escape(key)}`).find(".modal-body");
         return modal;
     });
 
diff --git a/static/js/lightbox.js b/static/js/lightbox.js
index 2070eb51d7..9374cd7251 100644
--- a/static/js/lightbox.js
+++ b/static/js/lightbox.js
@@ -281,7 +281,9 @@ exports.initialize = function () {
 
     $("#lightbox_overlay").on("click", ".image-list .image", function () {
         const $image_list = $(this).parent();
-        const $original_image = $(".message_row img[src='" + $(this).attr("data-src") + "']");
+        const $original_image = $(
+            `.message_row img[src='${CSS.escape($(this).attr("data-src"))}']`,
+        );
 
         exports.open($original_image);
 
diff --git a/static/js/message_edit.js b/static/js/message_edit.js
index c73a545da4..ba6401c641 100644
--- a/static/js/message_edit.js
+++ b/static/js/message_edit.js
@@ -345,9 +345,9 @@ function edit_message(row, raw_content) {
 
     form.on("keydown", handle_message_row_edit_keydown);
 
-    upload.feature_check($("#attach_files_" + rows.id(row)));
+    upload.feature_check($(`#attach_files_${CSS.escape(rows.id(row))}`));
 
-    const message_edit_stream = row.find("#select_stream_id_" + message.id);
+    const message_edit_stream = row.find(`#select_stream_id_${CSS.escape(message.id)}`);
     const stream_header_colorblock = row.find(".stream_header_colorblock");
     const message_edit_content = row.find("textarea.message_edit_content");
     const message_edit_topic = row.find("input.message_edit_topic");
@@ -381,7 +381,7 @@ function edit_message(row, raw_content) {
         new ClipboardJS(copy_message[0]);
     } else if (editability === editability_types.FULL) {
         copy_message.remove();
-        const edit_id = "#message_edit_content_" + rows.id(row);
+        const edit_id = `#message_edit_content_${CSS.escape(rows.id(row))}`;
         const listeners = resize.watch_manual_resize(edit_id);
         if (listeners) {
             currently_editing_messages.get(rows.id(row)).listeners = listeners;
@@ -576,7 +576,7 @@ exports.end_message_row_edit = function (row) {
 
         // Clean up resize event listeners
         const listeners = currently_editing_messages.get(message.id).listeners;
-        const edit_box = document.querySelector("#message_edit_content_" + message.id);
+        const edit_box = document.querySelector(`#message_edit_content_${CSS.escape(message.id)}`);
         if (listeners !== undefined) {
             // Event listeners to cleanup are only set in some edit types
             edit_box.removeEventListener("mousedown", listeners[0]);
@@ -670,7 +670,7 @@ exports.save_message_row_edit = function (row) {
         new_topic = row.find(".message_edit_topic").val();
         topic_changed = new_topic !== old_topic && new_topic.trim() !== "";
 
-        new_stream_id = Number.parseInt($("#select_stream_id_" + message_id).val(), 10);
+        new_stream_id = Number.parseInt($(`#select_stream_id_${CSS.escape(message_id)}`).val(), 10);
         stream_changed = new_stream_id !== old_stream_id;
     }
     // Editing a not-yet-acked message (because the original send attempt failed)
diff --git a/static/js/message_list_view.js b/static/js/message_list_view.js
index 4384675a96..4e39770ad4 100644
--- a/static/js/message_list_view.js
+++ b/static/js/message_list_view.js
@@ -659,7 +659,7 @@ class MessageListView {
             save_scroll_position();
 
             for (const message_group of message_actions.rerender_groups) {
-                const old_message_group = $("#" + message_group.message_group_id);
+                const old_message_group = $(`#${CSS.escape(message_group.message_group_id)}`);
                 // Remove the top date_row, we'll re-add it after rendering
                 old_message_group.prev(".date_row").remove();
 
diff --git a/static/js/notifications.js b/static/js/notifications.js
index 929dbc9baf..d1265078bd 100644
--- a/static/js/notifications.js
+++ b/static/js/notifications.js
@@ -190,7 +190,7 @@ function in_browser_notify(message, title, content, raw_operators, opts) {
         })
         .show();
 
-    $(".notification[data-message-id='" + message.id + "']")
+    $(`.notification[data-message-id='${CSS.escape(message.id)}']`)
         .expectOne()
         .data("narrow", {
             raw_operators,
diff --git a/static/js/overlays.js b/static/js/overlays.js
index b15b6e4d5f..d6764b9b5d 100644
--- a/static/js/overlays.js
+++ b/static/js/overlays.js
@@ -65,7 +65,7 @@ exports.active_modal = function () {
         blueslip.error("Programming error — Called active_modal when there is no modal open");
         return undefined;
     }
-    return "#" + $(".modal.in").attr("id");
+    return `#${CSS.escape($(".modal.in").attr("id"))}`;
 };
 
 exports.open_overlay = function (opts) {
diff --git a/static/js/popovers.js b/static/js/popovers.js
index b1858fc70e..b817989343 100644
--- a/static/js/popovers.js
+++ b/static/js/popovers.js
@@ -580,7 +580,7 @@ exports.render_actions_remind_popover = function (element, id) {
         });
         elt.popover("show");
         current_flatpickr_instance = $(
-            '.remind.custom[data-message-id="' + message.id + '"]',
+            `.remind.custom[data-message-id="${CSS.escape(message.id)}"]`,
         ).flatpickr({
             enableTime: true,
             clickOpens: false,
@@ -1226,7 +1226,7 @@ exports.register_click_handlers = function () {
     $("body").on("click", ".copy_link", function (e) {
         exports.hide_actions_popover();
         const message_id = $(this).attr("data-message-id");
-        const row = $("[zid='" + message_id + "']");
+        const row = $(`[zid='${CSS.escape(message_id)}']`);
         row.find(".alert-msg")
             .text(i18n.t("Copied!"))
             .css("display", "block")
diff --git a/static/js/portico/help.js b/static/js/portico/help.js
index 7951e9c781..1cd1f7bf67 100644
--- a/static/js/portico/help.js
+++ b/static/js/portico/help.js
@@ -34,12 +34,12 @@ function highlight_current_article() {
     }
 
     const hash = window.location.hash;
-    let article = $('.help .sidebar a[href="' + path + hash + '"]');
+    let article = $(`.help .sidebar a[href="${CSS.escape(path + hash)}"]`);
     if (!article.length) {
         // If there isn't an entry in the left sidebar that matches
         // the full URL+hash pair, instead highlight an entry in the
         // left sidebar that just matches the URL part.
-        article = $('.help .sidebar a[href="' + path + '"]');
+        article = $(`.help .sidebar a[href="${CSS.escape(path)}"]`);
     }
     // Highlight current article link and the heading of the same
     article.closest("ul").css("display", "block");
diff --git a/static/js/portico/integrations.js b/static/js/portico/integrations.js
index ca84e7bd6d..ef7e802dbb 100644
--- a/static/js/portico/integrations.js
+++ b/static/js/portico/integrations.js
@@ -63,11 +63,11 @@ function adjust_font_sizing() {
 function update_path() {
     let next_path;
     if (state.integration) {
-        next_path = $('.integration-lozenge[data-name="' + state.integration + '"]')
+        next_path = $(`.integration-lozenge[data-name="${CSS.escape(state.integration)}"]`)
             .closest("a")
             .attr("href");
     } else if (state.category) {
-        next_path = $('.integration-category[data-category="' + state.category + '"]')
+        next_path = $(`.integration-category[data-category="${CSS.escape(state.category)}"]`)
             .closest("a")
             .attr("href");
     } else {
@@ -82,7 +82,7 @@ function update_categories() {
     $(".integration-lozenges").css("opacity", 0);
 
     $(".integration-category").removeClass("selected");
-    $('[data-category="' + state.category + '"]').addClass("selected");
+    $(`[data-category="${CSS.escape(state.category)}"]`).addClass("selected");
 
     const $dropdown_label = $(".integration-categories-dropdown .dropdown-category-label");
     if (state.category === INITIAL_STATE.category) {
@@ -132,10 +132,12 @@ const update_integrations = _.debounce(() => {
 }, 50);
 
 function hide_catalog_show_integration() {
-    const $lozenge_icon = $(".integration-lozenge.integration-" + state.integration).clone(false);
+    const $lozenge_icon = $(
+        `.integration-lozenge.integration-${CSS.escape(state.integration)}`,
+    ).clone(false);
     $lozenge_icon.removeClass("legacy");
 
-    const categories = $(".integration-" + state.integration)
+    const categories = $(`.integration-${CSS.escape(state.integration)}`)
         .data("categories")
         .slice(1, -1)
         .split(",")
@@ -162,10 +164,10 @@ function hide_catalog_show_integration() {
             display: "flex",
         });
         $(".integration-instructions").css("display", "none");
-        $("#" + state.integration + ".integration-instructions .help-content").html(doc);
+        $(`#${CSS.escape(state.integration)}.integration-instructions .help-content`).html(doc);
         $("#integration-instruction-block .integration-lozenge").remove();
         $("#integration-instruction-block").append($lozenge_icon).css("display", "flex");
-        $(".integration-instructions#" + state.integration).css("display", "block");
+        $(`.integration-instructions#${CSS.escape(state.integration)}`).css("display", "block");
 
         $("html, body").animate({scrollTop: 0}, {duration: 200});
         $("#integration-instructions-group").animate({opacity: 1}, {duration: 300});
diff --git a/static/js/portico/landing-page.js b/static/js/portico/landing-page.js
index bd0eef25fb..9b50413def 100644
--- a/static/js/portico/landing-page.js
+++ b/static/js/portico/landing-page.js
@@ -156,7 +156,7 @@ const events = function () {
     // pop the last element to get the current section (eg. `features`).
     const location = window.location.pathname.replace(/\/#*$/, "").split(/\//).pop();
 
-    $("[data-on-page='" + location + "']").addClass("active");
+    $(`[data-on-page='${CSS.escape(location)}']`).addClass("active");
 
     $("body").on("click", (e) => {
         const $e = $(e.target);
diff --git a/static/js/portico/team.js b/static/js/portico/team.js
index e142cb0607..291bca7256 100644
--- a/static/js/portico/team.js
+++ b/static/js/portico/team.js
@@ -80,9 +80,9 @@ export default function render_tabs() {
             continue;
         }
         // Set as the loading template for now, and load when clicked.
-        $("#tab-" + tab_name).html($("#loading-template").html());
+        $(`#tab-${CSS.escape(tab_name)}`).html($("#loading-template").html());
 
-        $("#" + tab_name).on("click", () => {
+        $(`#${CSS.escape(tab_name)}`).on("click", () => {
             if (!loaded_repos.includes(repo_name)) {
                 const html = contributors_list
                     .filter((c) => c[repo_name])
@@ -100,7 +100,7 @@ export default function render_tabs() {
                     )
                     .join("");
 
-                $("#tab-" + tab_name).html(html);
+                $(`#tab-${CSS.escape(tab_name)}`).html(html);
 
                 loaded_repos.push(repo_name);
             }
diff --git a/static/js/reactions.js b/static/js/reactions.js
index f5bfd6ec72..d766b47ad7 100644
--- a/static/js/reactions.js
+++ b/static/js/reactions.js
@@ -195,14 +195,14 @@ exports.get_reaction_title_data = function (message_id, local_id) {
 };
 
 exports.get_reaction_section = function (message_id) {
-    const message_element = $(".message_table").find("[zid='" + message_id + "']");
+    const message_element = $(".message_table").find(`[zid='${CSS.escape(message_id)}']`);
     const section = message_element.find(".message_reactions");
     return section;
 };
 
 exports.find_reaction = function (message_id, local_id) {
     const reaction_section = exports.get_reaction_section(message_id);
-    const reaction = reaction_section.find("[data-reaction-id='" + local_id + "']");
+    const reaction = reaction_section.find(`[data-reaction-id='${CSS.escape(local_id)}']`);
     return reaction;
 };
 
diff --git a/static/js/recent_topics.js b/static/js/recent_topics.js
index 8609b421cc..6a6cf5860d 100644
--- a/static/js/recent_topics.js
+++ b/static/js/recent_topics.js
@@ -77,7 +77,7 @@ function revive_current_focus() {
         set_default_focus();
     } else {
         current_focus_elem = $("#recent_topics_filter_buttons").find(
-            "[data-filter='" + filter_button + "']",
+            `[data-filter='${CSS.escape(filter_button)}']`,
         );
         current_focus_elem.trigger("focus");
     }
@@ -211,7 +211,7 @@ function format_topic(topic_data) {
 function get_topic_row(topic_data) {
     const msg = message_store.get(topic_data.last_msg_id);
     const topic_key = get_topic_key(msg.stream_id, msg.topic);
-    return $("#" + $.escapeSelector("recent_topic:" + topic_key));
+    return $(`#${CSS.escape("recent_topic:" + topic_key)}`);
 }
 
 exports.process_topic_edit = function (old_stream_id, old_topic, new_topic, new_stream_id) {
@@ -326,7 +326,9 @@ exports.set_filter = function (filter) {
     // set `filters`.
 
     // Get the button which was clicked.
-    const filter_elem = $("#recent_topics_filter_buttons").find('[data-filter="' + filter + '"]');
+    const filter_elem = $("#recent_topics_filter_buttons").find(
+        `[data-filter="${CSS.escape(filter)}"]`,
+    );
 
     // If user clicks `All`, we clear all filters.
     if (filter === "all" && filters.size !== 0) {
@@ -350,7 +352,7 @@ function show_selected_filters() {
     } else {
         for (const filter of filters) {
             $("#recent_topics_filter_buttons")
-                .find('[data-filter="' + filter + '"]')
+                .find(`[data-filter="${CSS.escape(filter)}"]`)
                 .addClass("btn-recent-selected");
         }
     }
diff --git a/static/js/reminder.js b/static/js/reminder.js
index 5655ac990e..cf578e1c6f 100644
--- a/static/js/reminder.js
+++ b/static/js/reminder.js
@@ -106,7 +106,7 @@ exports.schedule_message = function (request) {
 };
 
 exports.do_set_reminder_for_message = function (message_id, timestamp) {
-    const row = $("[zid='" + message_id + "']");
+    const row = $(`[zid='${CSS.escape(message_id)}']`);
     function error() {
         row.find(".alert-msg")
             .text(i18n.t("Reminder not set!"))
diff --git a/static/js/rows.js b/static/js/rows.js
index 33808aac14..512c43b9d8 100644
--- a/static/js/rows.js
+++ b/static/js/rows.js
@@ -120,7 +120,7 @@ exports.get_table = function (table_name) {
         return $();
     }
 
-    return $("#" + table_name);
+    return $(`#${CSS.escape(table_name)}`);
 };
 
 exports.get_message_id = function (elem) {
diff --git a/static/js/settings.js b/static/js/settings.js
index 6d55cf2eda..ac1a653bfb 100644
--- a/static/js/settings.js
+++ b/static/js/settings.js
@@ -101,7 +101,9 @@ exports.launch = function (section) {
 };
 
 exports.set_settings_header = function (key) {
-    const header_text = $(`#settings_page .sidebar-list [data-section='${key}'] .text`).text();
+    const header_text = $(
+        `#settings_page .sidebar-list [data-section='${CSS.escape(key)}'] .text`,
+    ).text();
     if (header_text) {
         $(".settings-header h1 .section").text(" / " + header_text);
     } else {
diff --git a/static/js/settings_account.js b/static/js/settings_account.js
index 17c8a93791..d70a3cb361 100644
--- a/static/js/settings_account.js
+++ b/static/js/settings_account.js
@@ -108,7 +108,7 @@ function update_custom_profile_field(field, method) {
     }
 
     const spinner_element = $(
-        '.custom_user_field[data-field-id="' + field_id + '"] .custom-field-status',
+        `.custom_user_field[data-field-id="${CSS.escape(field_id)}"] .custom-field-status`,
     ).expectOne();
     settings_ui.do_settings_change(
         method,
@@ -230,7 +230,7 @@ exports.initialize_custom_user_type_fields = function (
         // pill container for that field and proceed further
         if (field.type === field_types.USER.id && (field_value_raw || is_editable)) {
             const pill_container = $(element_id)
-                .find('.custom_user_field[data-field-id="' + field.id + '"] .pill-container')
+                .find(`.custom_user_field[data-field-id="${CSS.escape(field.id)}"] .pill-container`)
                 .expectOne();
             const pills = user_pill.create_pills(pill_container);
 
diff --git a/static/js/settings_bots.js b/static/js/settings_bots.js
index 99f8ae4a37..4cf031be6e 100644
--- a/static/js/settings_bots.js
+++ b/static/js/settings_bots.js
@@ -42,7 +42,7 @@ const focus_tab = {
 };
 
 exports.get_bot_info_div = function (bot_id) {
-    const sel = '.bot_info[data-user-id="' + bot_id + '"]';
+    const sel = `.bot_info[data-user-id="${CSS.escape(bot_id)}"]`;
     return $(sel).expectOne();
 };
 
@@ -229,7 +229,7 @@ exports.set_up = function () {
     const selected_embedded_bot = "converter";
     $("#select_service_name").val(selected_embedded_bot); // TODO: Use 'select a bot'.
     $("#config_inputbox").children().hide();
-    $("[name*='" + selected_embedded_bot + "']").show();
+    $(`[name*='${CSS.escape(selected_embedded_bot)}']`).show();
 
     $("#download_botserverrc").on("click", function () {
         const OUTGOING_WEBHOOK_BOT_TYPE_INT = 3;
@@ -293,7 +293,7 @@ exports.set_up = function () {
             } else if (bot_type === EMBEDDED_BOT_TYPE) {
                 formData.append("service_name", service_name);
                 const config_data = {};
-                $("#config_inputbox [name*='" + service_name + "'] input").each(function () {
+                $(`#config_inputbox [name*='${CSS.escape(service_name)}'] input`).each(function () {
                     config_data[$(this).attr("name")] = $(this).val();
                 });
                 formData.append("config_data", JSON.stringify(config_data));
@@ -317,7 +317,7 @@ exports.set_up = function () {
                     $("#create_payload_url").val("");
                     $("#payload_url_inputbox").hide();
                     $("#config_inputbox").hide();
-                    $("[name*='" + service_name + "'] input").each(function () {
+                    $(`[name*='${CSS.escape(service_name)}'] input`).each(function () {
                         $(this).val("");
                     });
                     $("#create_bot_type").val(GENERIC_BOT_TYPE);
@@ -362,7 +362,7 @@ exports.set_up = function () {
     $("#select_service_name").on("change", () => {
         $("#config_inputbox").children().hide();
         const selected_bot = $("#select_service_name :selected").val();
-        $("[name*='" + selected_bot + "']").show();
+        $(`[name*='${CSS.escape(selected_bot)}']`).show();
     });
 
     $("#active_bots_list").on("click", "button.delete_bot", (e) => {
diff --git a/static/js/settings_display.js b/static/js/settings_display.js
index fa3066a6e8..946dc9e9ca 100644
--- a/static/js/settings_display.js
+++ b/static/js/settings_display.js
@@ -41,7 +41,7 @@ exports.set_up = function () {
 
     $("#twenty_four_hour_time").val(JSON.stringify(page_params.twenty_four_hour_time));
 
-    $(".emojiset_choice[value=" + page_params.emojiset + "]").prop("checked", true);
+    $(`.emojiset_choice[value="${CSS.escape(page_params.emojiset)}"]`).prop("checked", true);
 
     $("#default_language_modal [data-dismiss]").on("click", () => {
         overlays.close_modal("#default_language_modal");
@@ -49,7 +49,7 @@ exports.set_up = function () {
 
     const all_display_settings = settings_config.get_all_display_settings();
     for (const setting of all_display_settings.settings.user_display_settings) {
-        $("#" + setting).on("change", function () {
+        $(`#${CSS.escape(setting)}`).on("change", function () {
             const data = {};
             data[setting] = JSON.stringify($(this).prop("checked"));
 
diff --git a/static/js/settings_notifications.js b/static/js/settings_notifications.js
index 11bdd68346..22d3779d9b 100644
--- a/static/js/settings_notifications.js
+++ b/static/js/settings_notifications.js
@@ -156,7 +156,7 @@ exports.update_page = function () {
             continue;
         }
 
-        $("#" + setting).prop("checked", page_params[setting]);
+        $(`#${CSS.escape(setting)}`).prop("checked", page_params[setting]);
     }
     rerender_ui();
 };
diff --git a/static/js/settings_org.js b/static/js/settings_org.js
index b0ab076dd3..8c8dca3cab 100644
--- a/static/js/settings_org.js
+++ b/static/js/settings_org.js
@@ -210,11 +210,11 @@ const simple_dropdown_properties = [
 ];
 
 function set_property_dropdown_value(property_name) {
-    $("#id_" + property_name).val(get_property_value(property_name));
+    $(`#id_${CSS.escape(property_name)}`).val(get_property_value(property_name));
 }
 
 function change_element_block_display_property(elem_id, show_element) {
-    const elem = $("#" + elem_id);
+    const elem = $(`#${CSS.escape(elem_id)}`);
     if (show_element) {
         elem.parent().show();
     } else {
@@ -433,7 +433,7 @@ exports.sync_realm_settings = function (property) {
     } else if (property === "invite_required" || property === "invite_by_admins_only") {
         property = "user_invite_restriction";
     }
-    const element = $("#id_realm_" + property);
+    const element = $(`#id_realm_${CSS.escape(property)}`);
     if (element.length) {
         discard_property_element_changes(element);
     }
diff --git a/static/js/settings_panel_menu.js b/static/js/settings_panel_menu.js
index ebcd1b3759..8d2bdcdc95 100644
--- a/static/js/settings_panel_menu.js
+++ b/static/js/settings_panel_menu.js
@@ -47,7 +47,7 @@ class SettingsPanelMenu {
     }
 
     li_for_section(section) {
-        const li = $("#settings_overlay_container li[data-section='" + section + "']");
+        const li = $(`#settings_overlay_container li[data-section='${CSS.escape(section)}']`);
         return li;
     }
 
@@ -123,7 +123,7 @@ class SettingsPanelMenu {
 
     get_panel() {
         const section = this.curr_li.data("section");
-        const sel = "[data-name='" + section + "']";
+        const sel = `[data-name='${CSS.escape(section)}']`;
         const panel = $(".settings-section" + sel);
         return panel;
     }
diff --git a/static/js/settings_profile_fields.js b/static/js/settings_profile_fields.js
index d1c1a1bbc7..46a6ffdecc 100644
--- a/static/js/settings_profile_fields.js
+++ b/static/js/settings_profile_fields.js
@@ -209,8 +209,8 @@ function delete_choice_row(e) {
 
 function get_profile_field_info(id) {
     const info = {};
-    info.row = $("tr.profile-field-row[data-profile-field-id='" + id + "']");
-    info.form = $("tr.profile-field-form[data-profile-field-id='" + id + "']");
+    info.row = $(`tr.profile-field-row[data-profile-field-id='${CSS.escape(id)}']`);
+    info.form = $(`tr.profile-field-form[data-profile-field-id='${CSS.escape(id)}']`);
     return info;
 }
 
diff --git a/static/js/settings_ui.js b/static/js/settings_ui.js
index d789e33d22..9c37ac5f8b 100644
--- a/static/js/settings_ui.js
+++ b/static/js/settings_ui.js
@@ -77,13 +77,13 @@ exports.do_settings_change = function (request_method, url, data, status_element
 //   when main setting unchecked.
 exports.disable_sub_setting_onchange = function (is_checked, sub_setting_id, disable_on_uncheck) {
     if ((is_checked && disable_on_uncheck) || (!is_checked && !disable_on_uncheck)) {
-        $("#" + sub_setting_id).prop("disabled", false);
-        $("#" + sub_setting_id + "_label")
+        $(`#${CSS.escape(sub_setting_id)}`).prop("disabled", false);
+        $(`#${CSS.escape(sub_setting_id)}_label`)
             .parent()
             .removeClass("control-label-disabled");
     } else if ((is_checked && !disable_on_uncheck) || (!is_checked && disable_on_uncheck)) {
-        $("#" + sub_setting_id).prop("disabled", true);
-        $("#" + sub_setting_id + "_label")
+        $(`#${CSS.escape(sub_setting_id)}`).prop("disabled", true);
+        $(`#${CSS.escape(sub_setting_id)}_label`)
             .parent()
             .addClass("control-label-disabled");
     }
diff --git a/static/js/settings_user_groups.js b/static/js/settings_user_groups.js
index 69dedf5493..9b038b7993 100644
--- a/static/js/settings_user_groups.js
+++ b/static/js/settings_user_groups.js
@@ -57,14 +57,14 @@ exports.populate_user_groups = function () {
                 },
             }),
         );
-        const pill_container = $('.pill-container[data-group-pills="' + data.id + '"]');
+        const pill_container = $(`.pill-container[data-group-pills="${CSS.escape(data.id)}"]`);
         const pills = user_pill.create_pills(pill_container);
 
         function get_pill_user_ids() {
             return user_pill.get_user_ids(pills);
         }
 
-        const userg = $('div.user-group[id="' + data.id + '"]');
+        const userg = $(`div.user-group[id="${CSS.escape(data.id)}"]`);
         for (const user_id of data.members) {
             const user = people.get_by_user_id(user_id);
             user_pill.append_user(user, pills);
@@ -97,13 +97,13 @@ exports.populate_user_groups = function () {
             const group_data = user_groups.get_user_group_from_id(data.id);
             const original_group = Array.from(group_data.members);
             const same_groups = _.isEqual(_.sortBy(draft_group), _.sortBy(original_group));
-            const description = $("#user-groups #" + data.id + " .description")
+            const description = $(`#user-groups #${CSS.escape(data.id)} .description`)
                 .text()
                 .trim();
-            const name = $("#user-groups #" + data.id + " .name")
+            const name = $(`#user-groups #${CSS.escape(data.id)} .name`)
                 .text()
                 .trim();
-            const user_group_status = $("#user-groups #" + data.id + " .user-group-status");
+            const user_group_status = $(`#user-groups #${CSS.escape(data.id)} .user-group-status`);
 
             if (user_group_status.is(":visible")) {
                 return false;
@@ -123,9 +123,9 @@ exports.populate_user_groups = function () {
             if (!exports.can_edit(data.id)) {
                 return;
             }
-            const cancel_button = $("#user-groups #" + data.id + " .save-status.btn-danger");
-            const saved_button = $("#user-groups #" + data.id + " .save-status.sea-green");
-            const save_instructions = $("#user-groups #" + data.id + " .save-instructions");
+            const cancel_button = $(`#user-groups #${CSS.escape(data.id)} .save-status.btn-danger`);
+            const saved_button = $(`#user-groups #${CSS.escape(data.id)} .save-status.sea-green`);
+            const save_instructions = $(`#user-groups #${CSS.escape(data.id)} .save-instructions`);
 
             if (is_user_group_changed() && !cancel_button.is(":visible")) {
                 saved_button.fadeOut(0);
@@ -138,9 +138,9 @@ exports.populate_user_groups = function () {
         }
 
         function show_saved_button() {
-            const cancel_button = $("#user-groups #" + data.id + " .save-status.btn-danger");
-            const saved_button = $("#user-groups #" + data.id + " .save-status.sea-green");
-            const save_instructions = $("#user-groups #" + data.id + " .save-instructions");
+            const cancel_button = $(`#user-groups #${CSS.escape(data.id)} .save-status.btn-danger`);
+            const saved_button = $(`#user-groups #${CSS.escape(data.id)} .save-status.sea-green`);
+            const save_instructions = $(`#user-groups #${CSS.escape(data.id)} .save-instructions`);
             if (!saved_button.is(":visible")) {
                 cancel_button.fadeOut(0);
                 save_instructions.fadeOut(0);
@@ -175,12 +175,12 @@ exports.populate_user_groups = function () {
         }
 
         function save_name_desc() {
-            const user_group_status = $("#user-groups #" + data.id + " .user-group-status");
+            const user_group_status = $(`#user-groups #${CSS.escape(data.id)} .user-group-status`);
             const group_data = user_groups.get_user_group_from_id(data.id);
-            const description = $("#user-groups #" + data.id + " .description")
+            const description = $(`#user-groups #${CSS.escape(data.id)} .description`)
                 .text()
                 .trim();
-            const name = $("#user-groups #" + data.id + " .name")
+            const name = $(`#user-groups #${CSS.escape(data.id)} .name`)
                 .text()
                 .trim();
 
@@ -203,8 +203,10 @@ exports.populate_user_groups = function () {
                     xhr.responseText = JSON.stringify({msg: errors});
                     ui_report.error(i18n.t("Failed"), xhr, user_group_status);
                     update_cancel_button();
-                    $("#user-groups #" + data.id + " .name").text(group_data.name);
-                    $("#user-groups #" + data.id + " .description").text(group_data.description);
+                    $(`#user-groups #${CSS.escape(data.id)} .name`).text(group_data.name);
+                    $(`#user-groups #${CSS.escape(data.id)} .description`).text(
+                        group_data.description,
+                    );
                 },
             });
         }
@@ -219,7 +221,7 @@ exports.populate_user_groups = function () {
                 [".pill-container", ".name", ".description", ".input", ".delete"],
                 except_class,
             );
-            if ($(event.relatedTarget).closest("#user-groups #" + data.id).length) {
+            if ($(event.relatedTarget).closest(`#user-groups #${CSS.escape(data.id)}`).length) {
                 return blur_exceptions.some(
                     (class_name) => $(event.relatedTarget).closest(class_name).length,
                 );
@@ -236,7 +238,7 @@ exports.populate_user_groups = function () {
                 return;
             }
             if (
-                $(event.relatedTarget).closest("#user-groups #" + data.id) &&
+                $(event.relatedTarget).closest(`#user-groups #${CSS.escape(data.id)}`) &&
                 $(event.relatedTarget).closest(".save-status.btn-danger").length
             ) {
                 exports.reload();
@@ -246,21 +248,21 @@ exports.populate_user_groups = function () {
             save_members();
         }
 
-        $("#user-groups #" + data.id).on("blur", ".input", (event) => {
+        $(`#user-groups #${CSS.escape(data.id)}`).on("blur", ".input", (event) => {
             auto_save(".input", event);
         });
 
-        $("#user-groups #" + data.id).on("blur", ".name", (event) => {
+        $(`#user-groups #${CSS.escape(data.id)}`).on("blur", ".name", (event) => {
             auto_save(".name", event);
         });
-        $("#user-groups #" + data.id).on("input", ".name", () => {
+        $(`#user-groups #${CSS.escape(data.id)}`).on("input", ".name", () => {
             update_cancel_button();
         });
 
-        $("#user-groups #" + data.id).on("blur", ".description", (event) => {
+        $(`#user-groups #${CSS.escape(data.id)}`).on("blur", ".description", (event) => {
             auto_save(".description", event);
         });
-        $("#user-groups #" + data.id).on("input", ".description", () => {
+        $(`#user-groups #${CSS.escape(data.id)}`).on("input", ".description", () => {
             update_cancel_button();
         });
 
diff --git a/static/js/settings_users.js b/static/js/settings_users.js
index 3d5ef199ff..375e10afd5 100644
--- a/static/js/settings_users.js
+++ b/static/js/settings_users.js
@@ -66,7 +66,7 @@ function sort_last_active(a, b) {
 }
 
 function get_user_info_row(user_id) {
-    return $("tr.user_row[data-user-id='" + user_id + "']");
+    return $(`tr.user_row[data-user-id='${CSS.escape(user_id)}']`);
 }
 
 function set_user_role_dropdown(person) {
@@ -258,7 +258,7 @@ section.bots.create_table = () => {
         name: "admin_bot_list",
         get_item: bot_info,
         modifier: render_admin_user_list,
-        html_selector: (item) => `tr[data-user-id='${item}']`,
+        html_selector: (item) => `tr[data-user-id='${CSS.escape(item)}']`,
         filter: {
             element: $bots_table.closest(".settings-section").find(".search"),
             predicate(item, value) {
@@ -403,7 +403,7 @@ function open_human_form(person) {
     set_user_role_dropdown(person);
     if (!page_params.is_owner) {
         $("#user-role-select")
-            .find("option[value=" + settings_config.user_role_values.owner.code + "]")
+            .find(`option[value="${CSS.escape(settings_config.user_role_values.owner.code)}"]`)
             .hide();
     }
 
diff --git a/static/js/stream_color.js b/static/js/stream_color.js
index 932ff1d1e7..7d400cc424 100644
--- a/static/js/stream_color.js
+++ b/static/js/stream_color.js
@@ -39,8 +39,8 @@ function update_table_stream_color(table, stream_name, color) {
 }
 
 function update_stream_sidebar_swatch_color(id, color) {
-    $("#stream_sidebar_swatch_" + id).css("background-color", color);
-    $("#stream_sidebar_privacy_swatch_" + id).css("color", color);
+    $(`#stream_sidebar_swatch_${CSS.escape(id)}`).css("background-color", color);
+    $(`#stream_sidebar_privacy_swatch_${CSS.escape(id)}`).css("color", color);
 }
 
 function update_historical_message_color(stream_name, color) {
@@ -77,20 +77,23 @@ exports.update_stream_color = function (sub, color, opts) {
     sub.color = color;
     const stream_id = sub.stream_id;
     // The swatch in the subscription row header.
-    $(".stream-row[data-stream-id='" + stream_id + "'] .icon").css("background-color", color);
+    $(`.stream-row[data-stream-id='${CSS.escape(stream_id)}'] .icon`).css(
+        "background-color",
+        color,
+    );
     // The swatch in the color picker.
     exports.set_colorpicker_color(
         $(
-            "#subscription_overlay .subscription_settings[data-stream-id='" +
-                stream_id +
-                "'] .colorpicker",
+            `#subscription_overlay .subscription_settings[data-stream-id='${CSS.escape(
+                stream_id,
+            )}'] .colorpicker`,
         ),
         color,
     );
     $(
-        "#subscription_overlay .subscription_settings[data-stream-id='" +
-            stream_id +
-            "'] .large-icon",
+        `#subscription_overlay .subscription_settings[data-stream-id='${CSS.escape(
+            stream_id,
+        )}'] .large-icon`,
     ).css("color", color);
 
     if (opts.update_historical) {
diff --git a/static/js/stream_edit.js b/static/js/stream_edit.js
index 46545faa51..b196f1bc41 100644
--- a/static/js/stream_edit.js
+++ b/static/js/stream_edit.js
@@ -40,7 +40,9 @@ exports.setup_subscriptions_tab_hash = function (tab_key_value) {
 
 exports.settings_for_sub = function (sub) {
     return $(
-        "#subscription_overlay .subscription_settings[data-stream-id='" + sub.stream_id + "']",
+        `#subscription_overlay .subscription_settings[data-stream-id='${CSS.escape(
+            sub.stream_id,
+        )}']`,
     );
 };
 
@@ -168,7 +170,9 @@ function format_member_list_elem(person) {
 
 function get_subscriber_list(sub_row) {
     const stream_id_str = sub_row.data("stream-id");
-    return $('.subscription_settings[data-stream-id="' + stream_id_str + '"] .subscriber-list');
+    return $(
+        `.subscription_settings[data-stream-id="${CSS.escape(stream_id_str)}"] .subscriber-list`,
+    );
 }
 
 exports.update_stream_name = function (sub, new_name) {
@@ -294,9 +298,9 @@ function show_subscription_settings(sub) {
     stream_ui_updates.update_add_subscriptions_elements(sub);
 
     const container = $(
-        "#subscription_overlay .subscription_settings[data-stream-id='" +
-            stream_id +
-            "'] .pill-container",
+        `#subscription_overlay .subscription_settings[data-stream-id='${CSS.escape(
+            stream_id,
+        )}'] .pill-container`,
     );
 
     function create_item_from_text(text, current_items) {
@@ -345,7 +349,7 @@ function show_subscription_settings(sub) {
             return format_member_list_elem(item);
         },
         filter: {
-            element: $("[data-stream-id='" + stream_id + "'] .search"),
+            element: $(`[data-stream-id='${CSS.escape(stream_id)}'] .search`),
             predicate(item, value) {
                 const person = item;
 
@@ -433,7 +437,11 @@ function stream_is_muted_changed(e) {
     const sub_settings = exports.settings_for_sub(sub);
     const notification_checkboxes = sub_settings.find(".sub_notification_setting");
 
-    subs.set_muted(sub, e.target.checked, `#stream_change_property_status${sub.stream_id}`);
+    subs.set_muted(
+        sub,
+        e.target.checked,
+        `#stream_change_property_status${CSS.escape(sub.stream_id)}`,
+    );
     sub_settings.find(".mute-note").toggleClass("hide-mute-note", !sub.is_muted);
     notification_checkboxes.toggleClass("muted-sub", sub.is_muted);
     notification_checkboxes.find("input[type='checkbox']").prop("disabled", sub.is_muted);
@@ -447,7 +455,7 @@ exports.stream_setting_changed = function (e, from_notification_settings) {
     const sub = get_sub_for_target(e.target);
     const status_element = from_notification_settings
         ? $(e.target).closest(".subsection-parent").find(".alert-notification")
-        : $("#stream_change_property_status" + sub.stream_id);
+        : $(`#stream_change_property_status${CSS.escape(sub.stream_id)}`);
     const setting = e.target.name;
     if (!sub) {
         blueslip.error("undefined sub in stream_setting_changed()");
@@ -796,7 +804,7 @@ exports.initialize = function () {
         const sub = get_sub_for_target(e.target);
         // Makes sure we take the correct stream_row.
         const stream_row = $(
-            "#subscriptions_table div.stream-row[data-stream-id='" + sub.stream_id + "']",
+            `#subscriptions_table div.stream-row[data-stream-id='${CSS.escape(sub.stream_id)}']`,
         );
         subs.sub_or_unsub(sub, stream_row);
 
diff --git a/static/js/stream_events.js b/static/js/stream_events.js
index 42d842aea0..43be47c16a 100644
--- a/static/js/stream_events.js
+++ b/static/js/stream_events.js
@@ -7,7 +7,7 @@ const peer_data = require("./peer_data");
 // doing so is unnecessary with the current code.  Ideally, we'd do a
 // refactor to address that, however.
 function update_stream_setting(sub, value, setting) {
-    const setting_checkbox = $("#" + setting + "_" + sub.stream_id);
+    const setting_checkbox = $(`#${CSS.escape(setting)}_${CSS.escape(sub.stream_id)}`);
     setting_checkbox.prop("checked", value);
     sub[setting] = value;
 }
diff --git a/static/js/stream_muting.js b/static/js/stream_muting.js
index 6bf1680a8b..5c55240d2b 100644
--- a/static/js/stream_muting.js
+++ b/static/js/stream_muting.js
@@ -53,9 +53,9 @@ exports.update_is_muted = function (sub, value) {
     stream_list.set_in_home_view(sub.stream_id, !sub.is_muted);
 
     const is_muted_checkbox = $(
-        ".subscription_settings[data-stream-id='" +
-            sub.stream_id +
-            "'] #sub_is_muted_setting .sub_setting_control",
+        `.subscription_settings[data-stream-id='${CSS.escape(
+            sub.stream_id,
+        )}'] #sub_is_muted_setting .sub_setting_control`,
     );
     is_muted_checkbox.prop("checked", value);
 };
diff --git a/static/js/stream_popover.js b/static/js/stream_popover.js
index 2ff6c96f2b..a3288e35f6 100644
--- a/static/js/stream_popover.js
+++ b/static/js/stream_popover.js
@@ -186,7 +186,7 @@ function build_stream_popover(opts) {
     });
 
     $(elt).popover("show");
-    const popover = $(".streams_popover[data-stream-id=" + stream_id + "]");
+    const popover = $(`.streams_popover[data-stream-id="${CSS.escape(stream_id)}"]`);
 
     update_spectrum(popover, (colorpicker) => {
         colorpicker.spectrum(stream_color.sidebar_popover_colorpicker_options);
diff --git a/static/js/stream_ui_updates.js b/static/js/stream_ui_updates.js
index 022bb71508..ea55b79c97 100644
--- a/static/js/stream_ui_updates.js
+++ b/static/js/stream_ui_updates.js
@@ -82,7 +82,7 @@ exports.update_regular_sub_settings = function (sub) {
     if (!stream_edit.is_sub_settings_active(sub)) {
         return;
     }
-    const $settings = $(".subscription_settings[data-stream-id='" + sub.stream_id + "']");
+    const $settings = $(`.subscription_settings[data-stream-id='${CSS.escape(sub.stream_id)}']`);
     if (sub.subscribed) {
         if ($settings.find(".email-address").val().length === 0) {
             // Rerender stream email address, if not.
@@ -113,7 +113,7 @@ exports.update_notification_setting_checkbox = function (notification_name) {
         return;
     }
     const stream_id = stream_row.data("stream-id");
-    $(`#${notification_name}_${stream_id}`).prop(
+    $(`#${CSS.escape(notification_name)}_${CSS.escape(stream_id)}`).prop(
         "checked",
         stream_data.receives_notifications(stream_id, notification_name),
     );
diff --git a/static/js/subs.js b/static/js/subs.js
index 2c6b9e368b..2cb8e5615e 100644
--- a/static/js/subs.js
+++ b/static/js/subs.js
@@ -26,17 +26,19 @@ exports.show_subs_pane = {
 };
 
 exports.check_button_for_sub = function (sub) {
-    return $(".stream-row[data-stream-id='" + sub.stream_id + "'] .check");
+    return $(`.stream-row[data-stream-id='${CSS.escape(sub.stream_id)}'] .check`);
 };
 
 exports.row_for_stream_id = function (stream_id) {
-    return $(".stream-row[data-stream-id='" + stream_id + "']");
+    return $(`.stream-row[data-stream-id='${CSS.escape(stream_id)}']`);
 };
 
 exports.settings_button_for_sub = function (sub) {
     // We don't do expectOne() here, because this button is only
     // visible if the user has that stream selected in the streams UI.
-    return $(".subscription_settings[data-stream-id='" + sub.stream_id + "'] .subscribe-button");
+    return $(
+        `.subscription_settings[data-stream-id='${CSS.escape(sub.stream_id)}'] .subscribe-button`,
+    );
 };
 
 function get_row_data(row) {
@@ -284,7 +286,9 @@ exports.remove_stream = function (stream_id) {
 exports.update_settings_for_subscribed = function (sub) {
     stream_ui_updates.update_add_subscriptions_elements(sub);
     $(
-        ".subscription_settings[data-stream-id='" + sub.stream_id + "'] #preview-stream-button",
+        `.subscription_settings[data-stream-id='${CSS.escape(
+            sub.stream_id,
+        )}'] #preview-stream-button`,
     ).show();
 
     if (exports.is_sub_already_present(sub)) {
diff --git a/static/js/timerender.js b/static/js/timerender.js
index 9b928c748c..7447bfb718 100644
--- a/static/js/timerender.js
+++ b/static/js/timerender.js
@@ -193,7 +193,7 @@ exports.update_timestamps = function () {
 
         for (const entry of to_process) {
             const className = entry.className;
-            const elements = $("." + className);
+            const elements = $(`.${CSS.escape(className)}`);
             // The element might not exist any more (because it
             // was in the zfilt table, or because we added
             // messages above it and re-collapsed).
diff --git a/static/js/ui_util.js b/static/js/ui_util.js
index 0f8e2cef58..784d5a6410 100644
--- a/static/js/ui_util.js
+++ b/static/js/ui_util.js
@@ -4,7 +4,7 @@
 // dependencies other than jQuery.
 
 exports.change_tab_to = function (tabname) {
-    $('#gear-menu a[href="' + tabname + '"]').tab("show");
+    $(`#gear-menu a[href="${CSS.escape(tabname)}"]`).tab("show");
 };
 
 // https://stackoverflow.com/questions/4233265/contenteditable-set-caret-at-the-end-of-the-text-cross-browser
diff --git a/static/js/upload.js b/static/js/upload.js
index 219e95c3b6..8da345d4a5 100644
--- a/static/js/upload.js
+++ b/static/js/upload.js
@@ -58,27 +58,29 @@ exports.get_item = function (key, config) {
         }
         switch (key) {
             case "textarea":
-                return $("#message_edit_content_" + config.row);
+                return $(`#message_edit_content_${CSS.escape(config.row)}`);
             case "send_button":
-                return $("#message_edit_content_" + config.row)
+                return $(`#message_edit_content_${CSS.escape(config.row)}`)
                     .closest("#message_edit_form")
                     .find(".message_edit_save");
             case "send_status_identifier":
-                return "#message-edit-send-status-" + config.row;
+                return `#message-edit-send-status-${CSS.escape(config.row)}`;
             case "send_status":
-                return $("#message-edit-send-status-" + config.row);
+                return $(`#message-edit-send-status-${CSS.escape(config.row)}`);
             case "send_status_close_button":
-                return $("#message-edit-send-status-" + config.row).find(".send-status-close");
+                return $(`#message-edit-send-status-${CSS.escape(config.row)}`).find(
+                    ".send-status-close",
+                );
             case "send_status_message":
-                return $("#message-edit-send-status-" + config.row).find(".error-msg");
+                return $(`#message-edit-send-status-${CSS.escape(config.row)}`).find(".error-msg");
             case "file_input_identifier":
-                return "#message_edit_file_input_" + config.row;
+                return `#message_edit_file_input_${CSS.escape(config.row)}`;
             case "source":
                 return "message-edit-file-input";
             case "drag_drop_container":
                 return $("#message_edit_form");
             case "markdown_preview_hide_button":
-                return $("#undo_markdown_preview_" + config.row);
+                return $(`#undo_markdown_preview_${CSS.escape(config.row)}`);
             default:
                 throw new Error(`Invalid key name for mode "${config.mode}"`);
         }
diff --git a/tools/message-screenshot.js b/tools/message-screenshot.js
index 9960d8c169..b5939329fc 100644
--- a/tools/message-screenshot.js
+++ b/tools/message-screenshot.js
@@ -1,10 +1,11 @@
 "use strict";
 
-/* global $, navigate */
+/* global $, CSS, navigate */
 
 const path = require("path");
 
 const commander = require("commander");
+require("css.escape");
 const mkdirp = require("mkdirp");
 const puppeteer = require("puppeteer");
 
@@ -54,10 +55,10 @@ async function run() {
 
         // Navigate to message and capture screenshot
         await page.goto(`http://${host}/#narrow/near/${options.messageId}`);
-        const messageSelector = `#zfilt${options.messageId}`;
+        const messageSelector = `#zfilt${CSS.escape(options.messageId)}`;
         await page.waitForSelector(messageSelector);
         // remove unread marker and don't select message
-        const marker = `#zfilt${options.messageId} .unread_marker`;
+        const marker = `#zfilt${CSS.escape(options.messageId)} .unread_marker`;
         await page.evaluate((sel) => $(sel).remove(), marker);
         await page.evaluate(() => navigate.up());
         const messageBox = await page.$(messageSelector);
diff --git a/version.py b/version.py
index a0750341b2..7ef81e9a40 100644
--- a/version.py
+++ b/version.py
@@ -43,4 +43,4 @@ API_FEATURE_LEVEL = 38
 #   historical commits sharing the same major version, in which case a
 #   minor version bump suffices.
 
-PROVISION_VERSION = '124.1'
+PROVISION_VERSION = '124.2'
diff --git a/yarn.lock b/yarn.lock
index 61d8529c80..769cbe5644 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3619,6 +3619,11 @@ css-what@^3.2.1:
   resolved "https://registry.yarnpkg.com/css-what/-/css-what-3.4.2.tgz#ea7026fcb01777edbde52124e21f327e7ae950e4"
   integrity sha512-ACUm3L0/jiZTqfzRM3Hi9Q8eZqd6IK37mMWPLz9PJxkLWllYeRf+EHUSHYEtFop2Eqytaq1FizFVh7XfBnXCDQ==
 
+css.escape@^1.5.1:
+  version "1.5.1"
+  resolved "https://registry.yarnpkg.com/css.escape/-/css.escape-1.5.1.tgz#42e27d4fa04ae32f931a4b4d4191fa9cddee97cb"
+  integrity sha1-QuJ9T6BK4y+TGktNQZH6nN3ul8s=
+
 csscolorparser@~1.0.3:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/csscolorparser/-/csscolorparser-1.0.3.tgz#b34f391eea4da8f3e98231e2ccd8df9c041f171b"