diff --git a/docs/contributing/code-style.md b/docs/contributing/code-style.md
index f14dde4f03..eb9ec44959 100644
--- a/docs/contributing/code-style.md
+++ b/docs/contributing/code-style.md
@@ -236,7 +236,7 @@ functions or other arguments following them.
 Combine adjacent on-ready functions, if they are logically related.
 
 The best way to build complicated DOM elements is a Mustache template
-like `static/templates/message_reactions.handlebars`. For simpler things
+like `static/templates/message_reactions.hbs`. For simpler things
 you can use jQuery DOM building APIs like so:
 
     var new_tr = $('<tr />').attr('id', object.id);
diff --git a/docs/subsystems/html-templates.md b/docs/subsystems/html-templates.md
index 92b165cc0e..c70990a8d1 100644
--- a/docs/subsystems/html-templates.md
+++ b/docs/subsystems/html-templates.md
@@ -64,7 +64,7 @@ templates.
 
 In order to find the context definition, you should grep without using
 the file extension. For example, to find where
-`invite_subscription.handlebars` is rendered, you should run something
+`invite_subscription.hbs` is rendered, you should run something
 like this:
 
 ```
diff --git a/docs/tutorials/new-feature-tutorial.md b/docs/tutorials/new-feature-tutorial.md
index 14773f6461..5bd3b8e09f 100644
--- a/docs/tutorials/new-feature-tutorial.md
+++ b/docs/tutorials/new-feature-tutorial.md
@@ -42,7 +42,7 @@ organization in Zulip). The following files are involved in the process:
   consistent and correct.
 
 **Frontend**
-- `static/templates/settings/organization-permissions-admin.handlebars`: defines
+- `static/templates/settings/organization_permissions_admin.hbs`: defines
    the structure of the admin permissions page (checkboxes for each organization
    permission setting).
 - `static/js/settings_org.js`: handles organization setting form submission.
@@ -488,7 +488,7 @@ handled on the client.
 
 To add the checkbox to the admin page, modify the relevant template in
 `static/templates/settings/`, which can be
-`organization-permissions-admin.handlebars` or `organization-settings-admin.handlebars`
+`organization_permissions_admin.hbs` or `organization_settings_admin.hbs`
 (omitted here since it is relatively straightforward).
 
 Then add the new form control in `static/js/admin.js`.
diff --git a/frontend_tests/node_tests/compose.js b/frontend_tests/node_tests/compose.js
index 11bca18533..6168d79ea3 100644
--- a/frontend_tests/node_tests/compose.js
+++ b/frontend_tests/node_tests/compose.js
@@ -1086,7 +1086,7 @@ run_test('on_events', () => {
                 var called;
                 templates.render = function (template_name, context) {
                     called = true;
-                    assert.equal(template_name, 'compose-invite-users');
+                    assert.equal(template_name, 'compose_invite_users');
                     assert.equal(context.email, 'foo@bar.com');
                     assert.equal(context.name, 'Foo Barson');
                     return 'fake-compose-invite-user-template';
diff --git a/frontend_tests/node_tests/settings_org.js b/frontend_tests/node_tests/settings_org.js
index 3a52460cb5..5718178817 100644
--- a/frontend_tests/node_tests/settings_org.js
+++ b/frontend_tests/node_tests/settings_org.js
@@ -36,7 +36,7 @@ const _channel = {};
 
 const _templates = {
     render: function (name, data) {
-        if (name === 'settings/admin-realm-domains-list') {
+        if (name === 'settings/admin_realm_domains_list') {
             assert(data.realm_domain.domain);
             return 'stub-domains-list';
         }
diff --git a/frontend_tests/node_tests/templates.js b/frontend_tests/node_tests/templates.js
index 7e1908005d..814d5f64ab 100644
--- a/frontend_tests/node_tests/templates.js
+++ b/frontend_tests/node_tests/templates.js
@@ -11,7 +11,7 @@ const { window } = new JSDOM();
 global.$ = require('jquery')(window);
 
 // When writing these tests, the following command might be helpful:
-// ./tools/get-handlebar-vars static/templates/*.handlebars
+// ./tools/get-handlebar-vars static/templates/*.hbs
 
 function render(template_name, args) {
     return global.render_template(template_name, args);
@@ -20,13 +20,13 @@ function render(template_name, args) {
 run_test('finding_partials', () => {
     var fns = global.find_included_partials('settings_tab');
     assert.deepEqual(fns, [
-        'settings/account-settings',
-        'settings/display-settings',
-        'settings/notification-settings',
-        'settings/bot-settings',
-        'settings/alert-word-settings',
-        'settings/attachments-settings',
-        'settings/muted-topics-settings',
+        'settings/account_settings',
+        'settings/display_settings',
+        'settings/notification_settings',
+        'settings/bot_settings',
+        'settings/alert_word_settings',
+        'settings/attachments_settings',
+        'settings/muted_topics_settings',
     ]);
 });
 
@@ -91,7 +91,7 @@ run_test('admin_realm_domains_list', () => {
             allow_subdomains: true,
         },
     };
-    html += render("settings/admin-realm-domains-list", args);
+    html += render("settings/admin_realm_domains_list", args);
     html += "</table>";
 
     var button = $(html).find('.button');
@@ -115,7 +115,7 @@ run_test('admin_realm_dropdown_stream_list', () => {
             stream_id: 18,
         },
     };
-    html += render("settings/admin-realm-dropdown-stream-list", args);
+    html += render("settings/admin_realm_dropdown_stream_list", args);
     html += "</ul>";
 
     var link = $(html).find("a");
@@ -519,12 +519,12 @@ run_test('compose_invite_users', () => {
         name: 'Hamlet',
         can_subscribe_other_users: true,
     };
-    var html = render('compose-invite-users', args);
+    var html = render('compose_invite_users', args);
     var button = $(html).find("button").first();
     assert.equal(button.text(), "translated: Subscribe");
 
     args.can_subscribe_other_users = false;
-    html = render('compose-invite-users', args);
+    html = render('compose_invite_users', args);
     button = $(html).find("button").first();
     assert.equal(button.length, 0);
 });
@@ -590,7 +590,7 @@ run_test('compose_private_stream_alert', () => {
 run_test('custom_user_profile_field', () => {
     var field = {name: "GitHub user name", id: 2, hint: "Or link to profile"};
     var args = {field: field, field_value: {value: "@GitHub", rendered_value: "<p>@GitHub</p>"}, field_type: "text"};
-    var html = render('settings/custom-user-profile-field', args);
+    var html = render('settings/custom_user_profile_field', args);
     assert.equal($(html).attr('data-field-id'), 2);
     assert.equal($(html).find('.custom_user_field_value').val(), "@GitHub");
     assert.equal($(html).find('.field_hint').text(), "Or link to profile");
@@ -602,7 +602,7 @@ run_test('deactivate_stream_modal', () => {
         stream_name: "Public stream",
         stream_id: 1,
     };
-    var html = render('settings/deactivation-stream-modal', args);
+    var html = render('settings/deactivation_stream_modal', args);
 
     var modal_header = $(html).find("#deactivation_stream_modal_label");
     assert.equal(modal_header.text(), "translated: Delete stream " + args.stream_name);
@@ -1097,7 +1097,7 @@ run_test('revoke_invite_modal', () => {
     };
 
     var html = "<div>";
-    html += render('settings/revoke-invite-modal', args);
+    html += render('settings/revoke_invite_modal', args);
     html += "</div>";
     assert.equal($(html).find("p strong").text(), "iago@zulip.com");
 });
@@ -1471,7 +1471,7 @@ run_test('upload_space_stats', () => {
         percent_used: 50,
         upload_quota: "1 GB",
     };
-    var html = render('settings/upload-space-stats', args);
+    var html = render('settings/upload_space_stats', args);
     assert.equal($(html).text().trim(), "translated: Organization using 50% of 1 GB.\n    translated: Upgrade for more space.");
 
     args = {
@@ -1479,7 +1479,7 @@ run_test('upload_space_stats', () => {
         percent_used: 10,
         upload_quota: "5 GB",
     };
-    html = render('settings/upload-space-stats', args);
+    html = render('settings/upload_space_stats', args);
     assert.equal($(html).text().trim(), "translated: Organization using 10% of 5 GB.");
 });
 
@@ -1678,7 +1678,7 @@ run_test('edit_outgoing_webhook_service', () => {
         service: {base_url: "http://www.foo.bar",
                   interface: "1"},
     };
-    var html = render('settings/edit-outgoing-webhook-service', args);
+    var html = render('settings/edit_outgoing_webhook_service', args);
     assert.equal($(html).find('#edit_service_base_url').val(), args.service.base_url);
     assert.equal($(html).find('#edit_service_interface').val(), args.service.interface);
 });
@@ -1688,7 +1688,7 @@ run_test('edit_embedded_bot_service', () => {
         service: {service_name: "giphy",
                   config_data: {key: "abcd1234"}},
     };
-    var html = render('settings/edit-embedded-bot-service', args);
+    var html = render('settings/edit_embedded_bot_service', args);
     assert.equal($(html).find('#embedded_bot_key_edit').attr('name'), 'key');
     assert.equal($(html).find('#embedded_bot_key_edit').val(), 'abcd1234');
 });
diff --git a/frontend_tests/node_tests/voting_widget.js b/frontend_tests/node_tests/voting_widget.js
index e73fff3e3b..19de15c8ec 100644
--- a/frontend_tests/node_tests/voting_widget.js
+++ b/frontend_tests/node_tests/voting_widget.js
@@ -141,11 +141,11 @@ run_test('poll_data_holder my question', () => {
 run_test('activate another person poll', () => {
     people.is_my_user_id = return_false;
     templates.render = (template_name) => {
-        if (template_name === 'widgets/poll-widget') {
-            return 'widgets/poll-widget';
+        if (template_name === 'widgets/poll_widget') {
+            return 'widgets/poll_widget';
         }
-        if (template_name === 'widgets/poll-widget-results') {
-            return 'widgets/poll-widget-results';
+        if (template_name === 'widgets/poll_widget_results') {
+            return 'widgets/poll_widget_results';
         }
     };
 
@@ -234,8 +234,8 @@ run_test('activate another person poll', () => {
 
     poll_widget.activate(opts);
 
-    assert.equal(widget_elem.html(), 'widgets/poll-widget');
-    assert.equal(widget_option_container.html(), 'widgets/poll-widget-results');
+    assert.equal(widget_elem.html(), 'widgets/poll_widget');
+    assert.equal(widget_option_container.html(), 'widgets/poll_widget_results');
     assert.equal(poll_question_header.text(), 'What do you want?');
 
     const e = {
@@ -306,11 +306,11 @@ run_test('activate own poll', () => {
 
     people.is_my_user_id = return_true;
     templates.render = (template_name) => {
-        if (template_name === 'widgets/poll-widget') {
-            return 'widgets/poll-widget';
+        if (template_name === 'widgets/poll_widget') {
+            return 'widgets/poll_widget';
         }
-        if (template_name === 'widgets/poll-widget-results') {
-            return 'widgets/poll-widget-results';
+        if (template_name === 'widgets/poll_widget_results') {
+            return 'widgets/poll_widget_results';
         }
     };
 
@@ -396,8 +396,8 @@ run_test('activate own poll', () => {
 
     poll_widget.activate(opts);
 
-    assert.equal(widget_elem.html(), 'widgets/poll-widget');
-    assert.equal(widget_option_container.html(), 'widgets/poll-widget-results');
+    assert.equal(widget_elem.html(), 'widgets/poll_widget');
+    assert.equal(widget_option_container.html(), 'widgets/poll_widget_results');
     assert.equal(poll_question_header.text(), 'Where to go?');
 
     {
diff --git a/frontend_tests/zjsunit/render.js b/frontend_tests/zjsunit/render.js
index 77831e075b..7b45fa121a 100644
--- a/frontend_tests/zjsunit/render.js
+++ b/frontend_tests/zjsunit/render.js
@@ -68,7 +68,7 @@ exports.template_finder = (function () {
     // This class lets you find template files in our file system.
     // It may be slightly overkill for our flat directory system;
     // it might make more sense to just do something more like
-    // this: get_template_dir() + name + '.handlebars'
+    // this: get_template_dir() + name + '.hbs'
 
     var self = {};
 
@@ -76,12 +76,12 @@ exports.template_finder = (function () {
     var all_files = exports.walk(template_dir());
     var files = all_files
         .filter(function (file) {
-            return (/\.handlebars$/).test(file.name);
+            return (/\.hbs$/).test(file.name);
         })
         .map(function (file) {
             return {
                 url: file.url,
-                name: file.name.replace(/\.handlebars$/, ""),
+                name: file.name.replace(/\.hbs$/, ""),
             };
         });
 
diff --git a/static/js/attachments_ui.js b/static/js/attachments_ui.js
index a45314b064..0d1dde7dba 100644
--- a/static/js/attachments_ui.js
+++ b/static/js/attachments_ui.js
@@ -38,7 +38,7 @@ function set_upload_space_stats() {
         percent_used: exports.percentage_used_space(upload_space_used),
         upload_quota: attachments_ui.bytes_to_size(page_params.realm_upload_quota, true),
     };
-    var rendered_upload_stats_html = templates.render("settings/upload-space-stats", args);
+    var rendered_upload_stats_html = templates.render("settings/upload_space_stats", args);
     $("#attachment-stats-holder").html(rendered_upload_stats_html);
 }
 
diff --git a/static/js/compose.js b/static/js/compose.js
index 2f4c10ba60..a7f96a1389 100644
--- a/static/js/compose.js
+++ b/static/js/compose.js
@@ -835,7 +835,7 @@ exports.initialize = function () {
                         name: data.mentioned.full_name,
                         can_subscribe_other_users: page_params.can_subscribe_other_users,
                     };
-                    var new_row = templates.render("compose-invite-users", context);
+                    var new_row = templates.render("compose_invite_users", context);
                     error_area.append(new_row);
                 }
 
diff --git a/static/js/poll_widget.js b/static/js/poll_widget.js
index 15395f5aa3..a628b0b4b9 100644
--- a/static/js/poll_widget.js
+++ b/static/js/poll_widget.js
@@ -285,7 +285,7 @@ exports.activate = function (opts) {
     }
 
     function build_widget() {
-        var html = templates.render('widgets/poll-widget');
+        var html = templates.render('widgets/poll_widget');
         elem.html(html);
 
         elem.find('input.poll-question').on('keyup', function (e) {
@@ -346,7 +346,7 @@ exports.activate = function (opts) {
     function render_results() {
         var widget_data = poll_data.get_widget_data();
 
-        var html = templates.render('widgets/poll-widget-results', widget_data);
+        var html = templates.render('widgets/poll_widget_results', widget_data);
         elem.find('ul.poll-widget').html(html);
 
         elem.find("button.poll-vote").off('click').on('click', function (e) {
diff --git a/static/js/settings_account.js b/static/js/settings_account.js
index 59ad864d16..93b4c95712 100644
--- a/static/js/settings_account.js
+++ b/static/js/settings_account.js
@@ -110,7 +110,7 @@ exports.append_custom_profile_fields = function (element_id, user_id) {
             }
         }
 
-        var html = templates.render("settings/custom-user-profile-field", {
+        var html = templates.render("settings/custom_user_profile_field", {
             field: field,
             field_type: all_field_template_types[field.type],
             field_value: field_value,
diff --git a/static/js/settings_bots.js b/static/js/settings_bots.js
index 43f3ec6c32..f13ba21eee 100644
--- a/static/js/settings_bots.js
+++ b/static/js/settings_bots.js
@@ -401,12 +401,12 @@ exports.set_up = function () {
         $("#settings_page .edit_bot .edit-bot-owner select").val(bot.owner);
         var service = bot_data.get_services(bot_id)[0];
         if (bot.bot_type.toString() === OUTGOING_WEBHOOK_BOT_TYPE) {
-            $("#service_data").append(templates.render("settings/edit-outgoing-webhook-service",
+            $("#service_data").append(templates.render("settings/edit_outgoing_webhook_service",
                                                        {service: service}));
             $("#edit_service_interface").val(service.interface);
         }
         if (bot.bot_type.toString() === EMBEDDED_BOT_TYPE) {
-            $("#service_data").append(templates.render("settings/edit-embedded-bot-service",
+            $("#service_data").append(templates.render("settings/edit_embedded_bot_service",
                                                        {service: service}));
         }
 
diff --git a/static/js/settings_emoji.js b/static/js/settings_emoji.js
index 901376be93..9a57610bd5 100644
--- a/static/js/settings_emoji.js
+++ b/static/js/settings_emoji.js
@@ -34,7 +34,7 @@ function can_admin_emoji(emoji) {
 }
 
 exports.update_custom_emoji_ui = function () {
-    var rendered_tip = templates.render("settings/emoji-settings-tip", {
+    var rendered_tip = templates.render("settings/emoji_settings_tip", {
         realm_add_emoji_by_admins_only: page_params.realm_add_emoji_by_admins_only,
     });
     $('#emoji-settings').find('.emoji-settings-tip-container').html(rendered_tip);
diff --git a/static/js/settings_invites.js b/static/js/settings_invites.js
index 9f957c8460..855707fa9b 100644
--- a/static/js/settings_invites.js
+++ b/static/js/settings_invites.js
@@ -146,7 +146,7 @@ exports.on_load_success = function (invites_data, initialize_event_handlers) {
         meta.invite_id = $(e.currentTarget).attr("data-invite-id");
         meta.is_multiuse = $(e.currentTarget).attr("data-is-multiuse");
         var ctx = {is_multiuse: meta.is_multiuse === "true", email: email, referred_by: referred_by};
-        var rendered_revoke_modal = templates.render("settings/revoke-invite-modal", ctx);
+        var rendered_revoke_modal = templates.render("settings/revoke_invite_modal", ctx);
         $("#revoke_invite_modal_holder").html(rendered_revoke_modal);
         $("#revoke_invite_modal #do_revoke_invite_button").attr("data-invite-id", meta.invite_id);
         $("#revoke_invite_modal #do_revoke_invite_button").attr("data-is-multiuse", meta.is_multiuse);
diff --git a/static/js/settings_org.js b/static/js/settings_org.js
index 0c719784d4..d76020faf1 100644
--- a/static/js/settings_org.js
+++ b/static/js/settings_org.js
@@ -325,7 +325,7 @@ exports.populate_realm_domains = function (realm_domains) {
     var realm_domains_table_body = $("#realm_domains_table tbody").expectOne();
     realm_domains_table_body.find("tr").remove();
     _.each(realm_domains, function (realm_domain) {
-        realm_domains_table_body.append(templates.render("settings/admin-realm-domains-list", {realm_domain: realm_domain}));
+        realm_domains_table_body.append(templates.render("settings/admin_realm_domains_list", {realm_domain: realm_domain}));
     });
 };
 function sort_object_by_key(obj) {
@@ -357,7 +357,7 @@ function insert_tip_box() {
     if (page_params.is_admin) {
         return;
     }
-    var tip_box = templates.render("settings/organization-settings-tip", {is_admin: page_params.is_admin});
+    var tip_box = templates.render("settings/organization_settings_tip", {is_admin: page_params.is_admin});
     $(".organization-box").find(".settings-section:not(.can-edit)")
         .not("#emoji-settings")
         .not("#user-groups-admin")
@@ -388,7 +388,7 @@ exports.populate_notifications_stream_dropdown = function (stream_list) {
     list_render.create(dropdown_list_body, stream_list, {
         name: "admin-realm-notifications-stream-dropdown-list",
         modifier: function (item) {
-            return templates.render("settings/admin-realm-dropdown-stream-list", { stream: item });
+            return templates.render("settings/admin_realm_dropdown_stream_list", { stream: item });
         },
         filter: {
             element: search_input,
@@ -417,7 +417,7 @@ exports.populate_signup_notifications_stream_dropdown = function (stream_list) {
     list_render.create(dropdown_list_body, stream_list, {
         name: "admin-realm-signup-notifications-stream-dropdown-list",
         modifier: function (item) {
-            return templates.render("settings/admin-realm-dropdown-stream-list", { stream: item });
+            return templates.render("settings/admin_realm_dropdown_stream_list", { stream: item });
         },
         filter: {
             element: search_input,
diff --git a/static/js/settings_profile_fields.js b/static/js/settings_profile_fields.js
index 8b640faab3..2962bc8ee1 100644
--- a/static/js/settings_profile_fields.js
+++ b/static/js/settings_profile_fields.js
@@ -101,7 +101,7 @@ function update_choice_delete_btn(container, display_flag) {
 
 function create_choice_row(container) {
     var context = {};
-    var row = templates.render("settings/profile-field-choice", context);
+    var row = templates.render("settings/profile_field_choice", context);
     $(container).append(row);
 }
 
@@ -221,7 +221,7 @@ function set_up_choices_field_edit_form(profile_field, field_data) {
 
     _.each(choices_data, function (choice) {
         choice_list.append(
-            templates.render("settings/profile-field-choice", {
+            templates.render("settings/profile_field_choice", {
                 text: choice.text,
             })
         );
diff --git a/static/js/settings_users.js b/static/js/settings_users.js
index 700e2575fd..2049d89ebd 100644
--- a/static/js/settings_users.js
+++ b/static/js/settings_users.js
@@ -244,7 +244,7 @@ exports.set_up = function () {
 };
 
 function open_user_info_form_modal(person) {
-    var html = templates.render('user-info-form-modal', {
+    var html = templates.render('user_info_form_modal', {
         user_id: person.user_id,
         email: person.email,
         full_name: people.get_full_name(person.user_id),
diff --git a/static/js/stream_edit.js b/static/js/stream_edit.js
index 65f67f1a0e..459c864e23 100644
--- a/static/js/stream_edit.js
+++ b/static/js/stream_edit.js
@@ -617,7 +617,7 @@ exports.initialize = function () {
             return;
         }
         var stream_name = stream_data.maybe_get_stream_name(stream_id);
-        var deactivate_stream_modal = templates.render("settings/deactivation-stream-modal", {
+        var deactivate_stream_modal = templates.render("settings/deactivation_stream_modal", {
             stream_name: stream_name,
             stream_id: stream_id,
         });
diff --git a/static/js/stream_popover.js b/static/js/stream_popover.js
index f3f39a90f7..74e782838c 100644
--- a/static/js/stream_popover.js
+++ b/static/js/stream_popover.js
@@ -318,7 +318,7 @@ exports.register_stream_handlers = function () {
         e.preventDefault();
         e.stopPropagation();
         $(".left-sidebar-modal-holder").empty();
-        $(".left-sidebar-modal-holder").html(templates.render("unstar-messages-modal"));
+        $(".left-sidebar-modal-holder").html(templates.render("unstar_messages_modal"));
         $("#unstar-messages-modal").modal("show");
     });
 
diff --git a/static/js/templates.js b/static/js/templates.js
index a86547aebb..0dfcf08211 100644
--- a/static/js/templates.js
+++ b/static/js/templates.js
@@ -5,10 +5,10 @@ var exports = {};
 exports.render = function (name, arg) {
     var template;
     try {
-        template = require('../templates/' + name + '.handlebars');
+        template = require('../templates/' + name + '.hbs');
     } catch (_e) {
         throw new Error('Cannot find template static/templates/' + name
-            + '.handlebars.');
+            + '.hbs.');
     }
 
     return template(arg);
diff --git a/static/js/tictactoe_widget.js b/static/js/tictactoe_widget.js
index 89d7def044..333a956a7c 100644
--- a/static/js/tictactoe_widget.js
+++ b/static/js/tictactoe_widget.js
@@ -127,7 +127,7 @@ exports.activate = function (opts) {
 
     function render() {
         var widget_data = tictactoe_data.get_widget_data();
-        var html = templates.render('widgets/tictactoe-widget', widget_data);
+        var html = templates.render('widgets/tictactoe_widget', widget_data);
         elem.html(html);
 
         elem.find("button.tictactoe-square").on('click', function (e) {
diff --git a/static/js/todo_widget.js b/static/js/todo_widget.js
index 9a003be97f..e129eaae29 100644
--- a/static/js/todo_widget.js
+++ b/static/js/todo_widget.js
@@ -122,7 +122,7 @@ exports.activate = function (opts) {
     var task_data = exports.task_data_holder();
 
     function render() {
-        var html = templates.render('widgets/todo-widget');
+        var html = templates.render('widgets/todo_widget');
         elem.html(html);
 
         elem.find("button.add-task").on('click', function (e) {
@@ -149,7 +149,7 @@ exports.activate = function (opts) {
 
     function render_results() {
         var widget_data = task_data.get_widget_data();
-        var html = templates.render('widgets/todo-widget-tasks', widget_data);
+        var html = templates.render('widgets/todo_widget_tasks', widget_data);
         elem.find('ul.todo-widget').html(html);
         elem.find(".widget-error").text('');
 
diff --git a/static/js/zform.js b/static/js/zform.js
index 8e62d1393a..40fdee586f 100644
--- a/static/js/zform.js
+++ b/static/js/zform.js
@@ -64,7 +64,7 @@ exports.activate = function (opts) {
             choice.idx = idx;
         });
 
-        var html = templates.render('widgets/zform-choices', data);
+        var html = templates.render('widgets/zform_choices', data);
         var elem = $(html);
 
         elem.find('button').on('click', function (e) {
diff --git a/static/templates/actions_popover_content.handlebars b/static/templates/actions_popover_content.hbs
similarity index 100%
rename from static/templates/actions_popover_content.handlebars
rename to static/templates/actions_popover_content.hbs
diff --git a/static/templates/admin-settings-modals.handlebars b/static/templates/admin-settings-modals.handlebars
deleted file mode 100644
index 115f647779..0000000000
--- a/static/templates/admin-settings-modals.handlebars
+++ /dev/null
@@ -1,9 +0,0 @@
-{{ partial "settings/deactivation-user-modal" }}
-
-{{ partial "settings/realm-domains-modal" }}
-
-{{ partial "settings/revoke-invite-modal" }}
-
-{{ partial "settings/resend-invite-modal" }}
-
-<div id="user-info-form-modal-container"></div>
diff --git a/static/templates/admin_default_streams_list.handlebars b/static/templates/admin_default_streams_list.hbs
similarity index 100%
rename from static/templates/admin_default_streams_list.handlebars
rename to static/templates/admin_default_streams_list.hbs
diff --git a/static/templates/admin_emoji_list.handlebars b/static/templates/admin_emoji_list.hbs
similarity index 100%
rename from static/templates/admin_emoji_list.handlebars
rename to static/templates/admin_emoji_list.hbs
diff --git a/static/templates/admin_filter_list.handlebars b/static/templates/admin_filter_list.hbs
similarity index 100%
rename from static/templates/admin_filter_list.handlebars
rename to static/templates/admin_filter_list.hbs
diff --git a/static/templates/admin_invites_list.handlebars b/static/templates/admin_invites_list.hbs
similarity index 100%
rename from static/templates/admin_invites_list.handlebars
rename to static/templates/admin_invites_list.hbs
diff --git a/static/templates/admin_profile_field_list.handlebars b/static/templates/admin_profile_field_list.hbs
similarity index 98%
rename from static/templates/admin_profile_field_list.handlebars
rename to static/templates/admin_profile_field_list.hbs
index 0fd8fa0d04..106ea03551 100644
--- a/static/templates/admin_profile_field_list.handlebars
+++ b/static/templates/admin_profile_field_list.hbs
@@ -42,7 +42,7 @@
                     <hr />
                     <div class="edit_profile_field_choices_container">
                         {{#each choices}}
-                        {{partial "settings/profile-field-choice" }}
+                        {{partial "settings/profile_field_choice" }}
                         {{/each}}
                     </div>
                 </div>
diff --git a/static/templates/admin_settings_modals.hbs b/static/templates/admin_settings_modals.hbs
new file mode 100644
index 0000000000..b8b033cfee
--- /dev/null
+++ b/static/templates/admin_settings_modals.hbs
@@ -0,0 +1,9 @@
+{{ partial "settings/deactivation_user_modal" }}
+
+{{ partial "settings/realm_domains_modal" }}
+
+{{ partial "settings/revoke_invite_modal" }}
+
+{{ partial "settings/resend_invite_modal" }}
+
+<div id="user-info-form-modal-container"></div>
diff --git a/static/templates/admin_tab.handlebars b/static/templates/admin_tab.handlebars
deleted file mode 100644
index 41c1298854..0000000000
--- a/static/templates/admin_tab.handlebars
+++ /dev/null
@@ -1,30 +0,0 @@
-<div class="alert" id="organization-status"></div>
-<div id="revoke_invite_modal_holder"></div>
-
-{{ partial "admin-settings-modals"}}
-
-{{ partial "settings/organization-profile-admin" }}
-
-{{ partial "settings/organization-settings-admin" }}
-
-{{ partial "settings/organization-permissions-admin" }}
-
-{{ partial "settings/emoji-settings-admin" }}
-
-{{ partial "settings/user-list-admin" }}
-
-{{ partial "settings/deactivated-users-admin" }}
-
-{{ partial "settings/bot-list-admin" }}
-
-{{ partial "settings/default-streams-list-admin" }}
-
-{{ partial "settings/auth-methods-settings-admin" }}
-
-{{ partial "settings/linkifier-settings-admin" }}
-
-{{ partial "settings/invites-list-admin" }}
-
-{{ partial "user-groups-admin" }}
-
-{{ partial "settings/profile-field-settings-admin" }}
diff --git a/static/templates/admin_tab.hbs b/static/templates/admin_tab.hbs
new file mode 100644
index 0000000000..d562f51132
--- /dev/null
+++ b/static/templates/admin_tab.hbs
@@ -0,0 +1,30 @@
+<div class="alert" id="organization-status"></div>
+<div id="revoke_invite_modal_holder"></div>
+
+{{ partial "admin_settings_modals"}}
+
+{{ partial "settings/organization_profile_admin" }}
+
+{{ partial "settings/organization_settings_admin" }}
+
+{{ partial "settings/organization_permissions_admin" }}
+
+{{ partial "settings/emoji_settings_admin" }}
+
+{{ partial "settings/user_list_admin" }}
+
+{{ partial "settings/deactivated_users_admin" }}
+
+{{ partial "settings/bot_list_admin" }}
+
+{{ partial "settings/default_streams_list_admin" }}
+
+{{ partial "settings/auth_methods_settings_admin" }}
+
+{{ partial "settings/linkifier_settings_admin" }}
+
+{{ partial "settings/invites_list_admin" }}
+
+{{ partial "user_groups_admin" }}
+
+{{ partial "settings/profile_field_settings_admin" }}
diff --git a/static/templates/admin_user_group_list.handlebars b/static/templates/admin_user_group_list.hbs
similarity index 100%
rename from static/templates/admin_user_group_list.handlebars
rename to static/templates/admin_user_group_list.hbs
diff --git a/static/templates/admin_user_list.handlebars b/static/templates/admin_user_list.hbs
similarity index 100%
rename from static/templates/admin_user_list.handlebars
rename to static/templates/admin_user_list.hbs
diff --git a/static/templates/alert_word_settings_item.handlebars b/static/templates/alert_word_settings_item.hbs
similarity index 100%
rename from static/templates/alert_word_settings_item.handlebars
rename to static/templates/alert_word_settings_item.hbs
diff --git a/static/templates/all_messages_sidebar_actions.handlebars b/static/templates/all_messages_sidebar_actions.hbs
similarity index 100%
rename from static/templates/all_messages_sidebar_actions.handlebars
rename to static/templates/all_messages_sidebar_actions.hbs
diff --git a/static/templates/announce_stream_docs.handlebars b/static/templates/announce_stream_docs.hbs
similarity index 100%
rename from static/templates/announce_stream_docs.handlebars
rename to static/templates/announce_stream_docs.hbs
diff --git a/static/templates/archive_message_group.handlebars b/static/templates/archive_message_group.hbs
similarity index 100%
rename from static/templates/archive_message_group.handlebars
rename to static/templates/archive_message_group.hbs
diff --git a/static/templates/archive_recipient_row.handlebars b/static/templates/archive_recipient_row.hbs
similarity index 100%
rename from static/templates/archive_recipient_row.handlebars
rename to static/templates/archive_recipient_row.hbs
diff --git a/static/templates/bankruptcy_modal.handlebars b/static/templates/bankruptcy_modal.hbs
similarity index 100%
rename from static/templates/bankruptcy_modal.handlebars
rename to static/templates/bankruptcy_modal.hbs
diff --git a/static/templates/bookend.handlebars b/static/templates/bookend.hbs
similarity index 100%
rename from static/templates/bookend.handlebars
rename to static/templates/bookend.hbs
diff --git a/static/templates/bot_avatar_row.handlebars b/static/templates/bot_avatar_row.hbs
similarity index 100%
rename from static/templates/bot_avatar_row.handlebars
rename to static/templates/bot_avatar_row.hbs
diff --git a/static/templates/bot_owner_select.handlebars b/static/templates/bot_owner_select.hbs
similarity index 100%
rename from static/templates/bot_owner_select.handlebars
rename to static/templates/bot_owner_select.hbs
diff --git a/static/templates/compose_all_everyone.handlebars b/static/templates/compose_all_everyone.hbs
similarity index 100%
rename from static/templates/compose_all_everyone.handlebars
rename to static/templates/compose_all_everyone.hbs
diff --git a/static/templates/compose_announce.handlebars b/static/templates/compose_announce.hbs
similarity index 100%
rename from static/templates/compose_announce.handlebars
rename to static/templates/compose_announce.hbs
diff --git a/static/templates/compose-invite-users.handlebars b/static/templates/compose_invite_users.hbs
similarity index 100%
rename from static/templates/compose-invite-users.handlebars
rename to static/templates/compose_invite_users.hbs
diff --git a/static/templates/compose_not_subscribed.handlebars b/static/templates/compose_not_subscribed.hbs
similarity index 100%
rename from static/templates/compose_not_subscribed.handlebars
rename to static/templates/compose_not_subscribed.hbs
diff --git a/static/templates/compose_notification.handlebars b/static/templates/compose_notification.hbs
similarity index 100%
rename from static/templates/compose_notification.handlebars
rename to static/templates/compose_notification.hbs
diff --git a/static/templates/compose_private_stream_alert.handlebars b/static/templates/compose_private_stream_alert.hbs
similarity index 100%
rename from static/templates/compose_private_stream_alert.handlebars
rename to static/templates/compose_private_stream_alert.hbs
diff --git a/static/templates/confirm_delete_user.handlebars b/static/templates/confirm_delete_user.hbs
similarity index 100%
rename from static/templates/confirm_delete_user.handlebars
rename to static/templates/confirm_delete_user.hbs
diff --git a/static/templates/confirm_dialog.handlebars b/static/templates/confirm_dialog.hbs
similarity index 100%
rename from static/templates/confirm_dialog.handlebars
rename to static/templates/confirm_dialog.hbs
diff --git a/static/templates/default_language_modal.handlebars b/static/templates/default_language_modal.hbs
similarity index 100%
rename from static/templates/default_language_modal.handlebars
rename to static/templates/default_language_modal.hbs
diff --git a/static/templates/delete_topic_modal.handlebars b/static/templates/delete_topic_modal.hbs
similarity index 100%
rename from static/templates/delete_topic_modal.handlebars
rename to static/templates/delete_topic_modal.hbs
diff --git a/static/templates/draft.handlebars b/static/templates/draft.hbs
similarity index 100%
rename from static/templates/draft.handlebars
rename to static/templates/draft.hbs
diff --git a/static/templates/draft_table_body.handlebars b/static/templates/draft_table_body.hbs
similarity index 100%
rename from static/templates/draft_table_body.handlebars
rename to static/templates/draft_table_body.hbs
diff --git a/static/templates/edit_bot.handlebars b/static/templates/edit_bot.hbs
similarity index 100%
rename from static/templates/edit_bot.handlebars
rename to static/templates/edit_bot.hbs
diff --git a/static/templates/edited_notice.handlebars b/static/templates/edited_notice.hbs
similarity index 100%
rename from static/templates/edited_notice.handlebars
rename to static/templates/edited_notice.hbs
diff --git a/static/templates/email_address_hint.handlebars b/static/templates/email_address_hint.hbs
similarity index 100%
rename from static/templates/email_address_hint.handlebars
rename to static/templates/email_address_hint.hbs
diff --git a/static/templates/embedded_bot_config_item.handlebars b/static/templates/embedded_bot_config_item.hbs
similarity index 100%
rename from static/templates/embedded_bot_config_item.handlebars
rename to static/templates/embedded_bot_config_item.hbs
diff --git a/static/templates/emoji_popover.handlebars b/static/templates/emoji_popover.hbs
similarity index 100%
rename from static/templates/emoji_popover.handlebars
rename to static/templates/emoji_popover.hbs
diff --git a/static/templates/emoji_popover_content.handlebars b/static/templates/emoji_popover_content.hbs
similarity index 100%
rename from static/templates/emoji_popover_content.handlebars
rename to static/templates/emoji_popover_content.hbs
diff --git a/static/templates/emoji_popover_emoji.handlebars b/static/templates/emoji_popover_emoji.hbs
similarity index 100%
rename from static/templates/emoji_popover_emoji.handlebars
rename to static/templates/emoji_popover_emoji.hbs
diff --git a/static/templates/emoji_popover_search_results.handlebars b/static/templates/emoji_popover_search_results.hbs
similarity index 100%
rename from static/templates/emoji_popover_search_results.handlebars
rename to static/templates/emoji_popover_search_results.hbs
diff --git a/static/templates/emoji_showcase.handlebars b/static/templates/emoji_showcase.hbs
similarity index 100%
rename from static/templates/emoji_showcase.handlebars
rename to static/templates/emoji_showcase.hbs
diff --git a/static/templates/feedback_container.handlebars b/static/templates/feedback_container.hbs
similarity index 100%
rename from static/templates/feedback_container.handlebars
rename to static/templates/feedback_container.hbs
diff --git a/static/templates/group_pms.handlebars b/static/templates/group_pms.hbs
similarity index 100%
rename from static/templates/group_pms.handlebars
rename to static/templates/group_pms.hbs
diff --git a/static/templates/hotspot_overlay.handlebars b/static/templates/hotspot_overlay.hbs
similarity index 100%
rename from static/templates/hotspot_overlay.handlebars
rename to static/templates/hotspot_overlay.hbs
diff --git a/static/templates/input_pill.handlebars b/static/templates/input_pill.hbs
similarity index 100%
rename from static/templates/input_pill.handlebars
rename to static/templates/input_pill.hbs
diff --git a/static/templates/intro_reply_hotspot.handlebars b/static/templates/intro_reply_hotspot.hbs
similarity index 100%
rename from static/templates/intro_reply_hotspot.handlebars
rename to static/templates/intro_reply_hotspot.hbs
diff --git a/static/templates/invitation_failed_error.handlebars b/static/templates/invitation_failed_error.hbs
similarity index 100%
rename from static/templates/invitation_failed_error.handlebars
rename to static/templates/invitation_failed_error.hbs
diff --git a/static/templates/invite_subscription.handlebars b/static/templates/invite_subscription.hbs
similarity index 100%
rename from static/templates/invite_subscription.handlebars
rename to static/templates/invite_subscription.hbs
diff --git a/static/templates/loader.handlebars b/static/templates/loader.hbs
similarity index 100%
rename from static/templates/loader.handlebars
rename to static/templates/loader.hbs
diff --git a/static/templates/me_message.handlebars b/static/templates/me_message.hbs
similarity index 100%
rename from static/templates/me_message.handlebars
rename to static/templates/me_message.hbs
diff --git a/static/templates/message_avatar.handlebars b/static/templates/message_avatar.hbs
similarity index 100%
rename from static/templates/message_avatar.handlebars
rename to static/templates/message_avatar.hbs
diff --git a/static/templates/message_body.handlebars b/static/templates/message_body.hbs
similarity index 100%
rename from static/templates/message_body.handlebars
rename to static/templates/message_body.hbs
diff --git a/static/templates/message_controls.handlebars b/static/templates/message_controls.hbs
similarity index 100%
rename from static/templates/message_controls.handlebars
rename to static/templates/message_controls.hbs
diff --git a/static/templates/message_edit_form.handlebars b/static/templates/message_edit_form.hbs
similarity index 100%
rename from static/templates/message_edit_form.handlebars
rename to static/templates/message_edit_form.hbs
diff --git a/static/templates/message_edit_history.handlebars b/static/templates/message_edit_history.hbs
similarity index 100%
rename from static/templates/message_edit_history.handlebars
rename to static/templates/message_edit_history.hbs
diff --git a/static/templates/message_group.handlebars b/static/templates/message_group.hbs
similarity index 100%
rename from static/templates/message_group.handlebars
rename to static/templates/message_group.hbs
diff --git a/static/templates/message_reaction.handlebars b/static/templates/message_reaction.hbs
similarity index 100%
rename from static/templates/message_reaction.handlebars
rename to static/templates/message_reaction.hbs
diff --git a/static/templates/message_reactions.handlebars b/static/templates/message_reactions.hbs
similarity index 100%
rename from static/templates/message_reactions.handlebars
rename to static/templates/message_reactions.hbs
diff --git a/static/templates/mobile_message_buttons_popover.handlebars b/static/templates/mobile_message_buttons_popover.hbs
similarity index 100%
rename from static/templates/mobile_message_buttons_popover.handlebars
rename to static/templates/mobile_message_buttons_popover.hbs
diff --git a/static/templates/mobile_message_buttons_popover_content.handlebars b/static/templates/mobile_message_buttons_popover_content.hbs
similarity index 100%
rename from static/templates/mobile_message_buttons_popover_content.handlebars
rename to static/templates/mobile_message_buttons_popover_content.hbs
diff --git a/static/templates/more_topics.handlebars b/static/templates/more_topics.hbs
similarity index 100%
rename from static/templates/more_topics.handlebars
rename to static/templates/more_topics.hbs
diff --git a/static/templates/muted_topic_ui_row.handlebars b/static/templates/muted_topic_ui_row.hbs
similarity index 100%
rename from static/templates/muted_topic_ui_row.handlebars
rename to static/templates/muted_topic_ui_row.hbs
diff --git a/static/templates/new_stream_users.handlebars b/static/templates/new_stream_users.hbs
similarity index 100%
rename from static/templates/new_stream_users.handlebars
rename to static/templates/new_stream_users.hbs
diff --git a/static/templates/no_arrow_popover.handlebars b/static/templates/no_arrow_popover.hbs
similarity index 100%
rename from static/templates/no_arrow_popover.handlebars
rename to static/templates/no_arrow_popover.hbs
diff --git a/static/templates/non_editable_user_group.handlebars b/static/templates/non_editable_user_group.hbs
similarity index 100%
rename from static/templates/non_editable_user_group.handlebars
rename to static/templates/non_editable_user_group.hbs
diff --git a/static/templates/notification.handlebars b/static/templates/notification.hbs
similarity index 100%
rename from static/templates/notification.handlebars
rename to static/templates/notification.hbs
diff --git a/static/templates/recipient_row.handlebars b/static/templates/recipient_row.hbs
similarity index 100%
rename from static/templates/recipient_row.handlebars
rename to static/templates/recipient_row.hbs
diff --git a/static/templates/remind_me_popover_content.handlebars b/static/templates/remind_me_popover_content.hbs
similarity index 100%
rename from static/templates/remind_me_popover_content.handlebars
rename to static/templates/remind_me_popover_content.hbs
diff --git a/static/templates/settings/account-settings.handlebars b/static/templates/settings/account_settings.hbs
similarity index 100%
rename from static/templates/settings/account-settings.handlebars
rename to static/templates/settings/account_settings.hbs
diff --git a/static/templates/settings/admin_auth_methods_list.handlebars b/static/templates/settings/admin_auth_methods_list.hbs
similarity index 100%
rename from static/templates/settings/admin_auth_methods_list.handlebars
rename to static/templates/settings/admin_auth_methods_list.hbs
diff --git a/static/templates/settings/admin-realm-domains-list.handlebars b/static/templates/settings/admin_realm_domains_list.hbs
similarity index 100%
rename from static/templates/settings/admin-realm-domains-list.handlebars
rename to static/templates/settings/admin_realm_domains_list.hbs
diff --git a/static/templates/settings/admin-realm-dropdown-stream-list.handlebars b/static/templates/settings/admin_realm_dropdown_stream_list.hbs
similarity index 100%
rename from static/templates/settings/admin-realm-dropdown-stream-list.handlebars
rename to static/templates/settings/admin_realm_dropdown_stream_list.hbs
diff --git a/static/templates/settings/alert-word-settings.handlebars b/static/templates/settings/alert_word_settings.hbs
similarity index 100%
rename from static/templates/settings/alert-word-settings.handlebars
rename to static/templates/settings/alert_word_settings.hbs
diff --git a/static/templates/settings/attachments-settings.handlebars b/static/templates/settings/attachments_settings.hbs
similarity index 100%
rename from static/templates/settings/attachments-settings.handlebars
rename to static/templates/settings/attachments_settings.hbs
diff --git a/static/templates/settings/auth-methods-settings-admin.handlebars b/static/templates/settings/auth_methods_settings_admin.hbs
similarity index 93%
rename from static/templates/settings/auth-methods-settings-admin.handlebars
rename to static/templates/settings/auth_methods_settings_admin.hbs
index 4d787014eb..356c57ac47 100644
--- a/static/templates/settings/auth-methods-settings-admin.handlebars
+++ b/static/templates/settings/auth_methods_settings_admin.hbs
@@ -3,7 +3,7 @@
         <div id="org-auth_settings" class="admin-table-wrapper org-subsection-parent">
             <div class ="subsection-header">
                 <h3>{{t "Authentication methods" }}</h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "auth_settings" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "auth_settings" }}
             </div>
 
             <div>
diff --git a/static/templates/settings/bot-list-admin.handlebars b/static/templates/settings/bot_list_admin.hbs
similarity index 100%
rename from static/templates/settings/bot-list-admin.handlebars
rename to static/templates/settings/bot_list_admin.hbs
diff --git a/static/templates/settings/bot-settings.handlebars b/static/templates/settings/bot_settings.hbs
similarity index 100%
rename from static/templates/settings/bot-settings.handlebars
rename to static/templates/settings/bot_settings.hbs
diff --git a/static/templates/settings/custom-user-profile-field.handlebars b/static/templates/settings/custom_user_profile_field.hbs
similarity index 100%
rename from static/templates/settings/custom-user-profile-field.handlebars
rename to static/templates/settings/custom_user_profile_field.hbs
diff --git a/static/templates/settings/deactivate-realm-modal.handlebars b/static/templates/settings/deactivate_realm_modal.hbs
similarity index 100%
rename from static/templates/settings/deactivate-realm-modal.handlebars
rename to static/templates/settings/deactivate_realm_modal.hbs
diff --git a/static/templates/settings/deactivated-users-admin.handlebars b/static/templates/settings/deactivated_users_admin.hbs
similarity index 100%
rename from static/templates/settings/deactivated-users-admin.handlebars
rename to static/templates/settings/deactivated_users_admin.hbs
diff --git a/static/templates/settings/deactivation-stream-modal.handlebars b/static/templates/settings/deactivation_stream_modal.hbs
similarity index 100%
rename from static/templates/settings/deactivation-stream-modal.handlebars
rename to static/templates/settings/deactivation_stream_modal.hbs
diff --git a/static/templates/settings/deactivation-user-modal.handlebars b/static/templates/settings/deactivation_user_modal.hbs
similarity index 100%
rename from static/templates/settings/deactivation-user-modal.handlebars
rename to static/templates/settings/deactivation_user_modal.hbs
diff --git a/static/templates/settings/default-streams-list-admin.handlebars b/static/templates/settings/default_streams_list_admin.hbs
similarity index 100%
rename from static/templates/settings/default-streams-list-admin.handlebars
rename to static/templates/settings/default_streams_list_admin.hbs
diff --git a/static/templates/settings/dev_env_email_access.handlebars b/static/templates/settings/dev_env_email_access.hbs
similarity index 100%
rename from static/templates/settings/dev_env_email_access.handlebars
rename to static/templates/settings/dev_env_email_access.hbs
diff --git a/static/templates/settings/display-settings.handlebars b/static/templates/settings/display_settings.hbs
similarity index 100%
rename from static/templates/settings/display-settings.handlebars
rename to static/templates/settings/display_settings.hbs
diff --git a/static/templates/settings/edit-embedded-bot-service.handlebars b/static/templates/settings/edit_embedded_bot_service.hbs
similarity index 100%
rename from static/templates/settings/edit-embedded-bot-service.handlebars
rename to static/templates/settings/edit_embedded_bot_service.hbs
diff --git a/static/templates/settings/edit-outgoing-webhook-service.handlebars b/static/templates/settings/edit_outgoing_webhook_service.hbs
similarity index 100%
rename from static/templates/settings/edit-outgoing-webhook-service.handlebars
rename to static/templates/settings/edit_outgoing_webhook_service.hbs
diff --git a/static/templates/settings/emoji-settings-admin.handlebars b/static/templates/settings/emoji_settings_admin.hbs
similarity index 97%
rename from static/templates/settings/emoji-settings-admin.handlebars
rename to static/templates/settings/emoji_settings_admin.hbs
index b64b654fad..e6f18483ef 100644
--- a/static/templates/settings/emoji-settings-admin.handlebars
+++ b/static/templates/settings/emoji_settings_admin.hbs
@@ -1,6 +1,6 @@
 <div id="emoji-settings" data-name="emoji-settings" class="settings-section {{#if can_add_emojis}}can-edit{{/if}}">
     <div class="emoji-settings-tip-container">
-        {{partial "settings/emoji-settings-tip"}}
+        {{partial "settings/emoji_settings_tip"}}
     </div>
     <form class="form-horizontal admin-emoji-form {{#unless can_add_emojis}}hide{{/unless}}">
         <div class="add-new-emoji-box grey-box">
diff --git a/static/templates/settings/emoji-settings-tip.handlebars b/static/templates/settings/emoji_settings_tip.hbs
similarity index 100%
rename from static/templates/settings/emoji-settings-tip.handlebars
rename to static/templates/settings/emoji_settings_tip.hbs
diff --git a/static/templates/settings/invites-list-admin.handlebars b/static/templates/settings/invites_list_admin.hbs
similarity index 100%
rename from static/templates/settings/invites-list-admin.handlebars
rename to static/templates/settings/invites_list_admin.hbs
diff --git a/static/templates/settings/linkifier-settings-admin.handlebars b/static/templates/settings/linkifier_settings_admin.hbs
similarity index 100%
rename from static/templates/settings/linkifier-settings-admin.handlebars
rename to static/templates/settings/linkifier_settings_admin.hbs
diff --git a/static/templates/settings/muted-topics-settings.handlebars b/static/templates/settings/muted_topics_settings.hbs
similarity index 100%
rename from static/templates/settings/muted-topics-settings.handlebars
rename to static/templates/settings/muted_topics_settings.hbs
diff --git a/static/templates/settings/notification-settings.handlebars b/static/templates/settings/notification_settings.hbs
similarity index 100%
rename from static/templates/settings/notification-settings.handlebars
rename to static/templates/settings/notification_settings.hbs
diff --git a/static/templates/settings/organization-permissions-admin.handlebars b/static/templates/settings/organization_permissions_admin.hbs
similarity index 97%
rename from static/templates/settings/organization-permissions-admin.handlebars
rename to static/templates/settings/organization_permissions_admin.hbs
index e759b10f42..697d710aa6 100644
--- a/static/templates/settings/organization-permissions-admin.handlebars
+++ b/static/templates/settings/organization_permissions_admin.hbs
@@ -4,7 +4,7 @@
         <div id="org-org-join" class="org-subsection-parent">
             <div class="subsection-header">
                 <h3>{{t "Joining the organization" }}</h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "org-join" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "org-join" }}
             </div>
             <div class="m-10 inline-block organization-permissions-parent">
                 <div class="input-group">
@@ -36,7 +36,7 @@
         <div id="org-user-identity" class="org-subsection-parent">
             <div class="subsection-header">
                 <h3>{{t "User identity" }}</h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "user-identity" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "user-identity" }}
             </div>
             <div class="inline-block organization-permissions-parent">
                 {{partial "settings/settings_checkbox"
@@ -62,7 +62,7 @@
         <div id="org-other-permissions" class="org-subsection-parent">
             <div class="subsection-header">
                 <h3>{{t "Other permissions" }}</h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "other-permissions" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "other-permissions" }}
             </div>
             <div class="m-10 inline-block organization-permissions-parent">
                 <div class="input-group">
diff --git a/static/templates/settings/organization-profile-admin.handlebars b/static/templates/settings/organization_profile_admin.hbs
similarity index 98%
rename from static/templates/settings/organization-profile-admin.handlebars
rename to static/templates/settings/organization_profile_admin.hbs
index 51a22f98aa..c7bd4c5384 100644
--- a/static/templates/settings/organization-profile-admin.handlebars
+++ b/static/templates/settings/organization_profile_admin.hbs
@@ -9,7 +9,7 @@
                         <i class="fa fa-question-circle-o" aria-hidden="true"></i>
                     </a>
                 </h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "org-profile" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "org-profile" }}
             </div>
 
             <div class="organization-settings-parent">
@@ -116,7 +116,7 @@
                     {{t 'Deactivate organization' }}
                 </button>
             </div>
-            {{ partial "settings/deactivate-realm-modal"}}
+            {{ partial "settings/deactivate_realm_modal"}}
         </div>
     </form>
 </div>
diff --git a/static/templates/settings/organization-settings-admin.handlebars b/static/templates/settings/organization_settings_admin.hbs
similarity index 98%
rename from static/templates/settings/organization-settings-admin.handlebars
rename to static/templates/settings/organization_settings_admin.hbs
index c60a4c6dc7..3f8e488a8d 100644
--- a/static/templates/settings/organization-settings-admin.handlebars
+++ b/static/templates/settings/organization_settings_admin.hbs
@@ -10,7 +10,7 @@
                         <i class="fa fa-question-circle-o" aria-hidden="true"></i>
                     </a>
                 </h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "msg-editing" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "msg-editing" }}
             </div>
             <div class="inline-block organization-settings-parent">
                 <div class="input-group">
@@ -72,7 +72,7 @@
         <div id="org-notifications" class="org-subsection-parent">
             <div class="subsection-header">
                 <h3>{{t "Notifications" }}</h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "notifications" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "notifications" }}
             </div>
             <div class="inline-block organization-settings-parent">
                 {{partial "settings/settings_checkbox"
@@ -152,7 +152,7 @@
         <div id="org-user-defaults" class="org-subsection-parent">
             <div class="subsection-header">
                 <h3>{{t "Default user settings" }}</h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "user-defaults" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "user-defaults" }}
             </div>
             <p>{{t "Default settings for new users joining this organization." }}</p>
             <div class="inline-block organization-settings-parent">
@@ -175,7 +175,7 @@
         <div id="org-other-settings" class="org-subsection-parent">
             <div class="subsection-header">
                 <h3>{{t "Other settings" }}</h3>
-                {{ partial "settings/settings-save-discard-widget" "section_name" "other-settings" }}
+                {{ partial "settings/settings_save_discard_widget" "section_name" "other-settings" }}
             </div>
             <div class="inline-block organization-settings-parent">
                 <div class="input-group">
diff --git a/static/templates/settings/organization-settings-tip.handlebars b/static/templates/settings/organization_settings_tip.hbs
similarity index 100%
rename from static/templates/settings/organization-settings-tip.handlebars
rename to static/templates/settings/organization_settings_tip.hbs
diff --git a/static/templates/settings/profile-field-choice.handlebars b/static/templates/settings/profile_field_choice.hbs
similarity index 100%
rename from static/templates/settings/profile-field-choice.handlebars
rename to static/templates/settings/profile_field_choice.hbs
diff --git a/static/templates/settings/profile-field-settings-admin.handlebars b/static/templates/settings/profile_field_settings_admin.hbs
similarity index 100%
rename from static/templates/settings/profile-field-settings-admin.handlebars
rename to static/templates/settings/profile_field_settings_admin.hbs
diff --git a/static/templates/settings/realm-domains-modal.handlebars b/static/templates/settings/realm_domains_modal.hbs
similarity index 100%
rename from static/templates/settings/realm-domains-modal.handlebars
rename to static/templates/settings/realm_domains_modal.hbs
diff --git a/static/templates/settings/resend-invite-modal.handlebars b/static/templates/settings/resend_invite_modal.hbs
similarity index 100%
rename from static/templates/settings/resend-invite-modal.handlebars
rename to static/templates/settings/resend_invite_modal.hbs
diff --git a/static/templates/settings/revoke-invite-modal.handlebars b/static/templates/settings/revoke_invite_modal.hbs
similarity index 100%
rename from static/templates/settings/revoke-invite-modal.handlebars
rename to static/templates/settings/revoke_invite_modal.hbs
diff --git a/static/templates/settings/settings_checkbox.handlebars b/static/templates/settings/settings_checkbox.hbs
similarity index 100%
rename from static/templates/settings/settings_checkbox.handlebars
rename to static/templates/settings/settings_checkbox.hbs
diff --git a/static/templates/settings/settings-save-discard-widget.handlebars b/static/templates/settings/settings_save_discard_widget.hbs
similarity index 100%
rename from static/templates/settings/settings-save-discard-widget.handlebars
rename to static/templates/settings/settings_save_discard_widget.hbs
diff --git a/static/templates/settings/upload-space-stats.handlebars b/static/templates/settings/upload_space_stats.hbs
similarity index 100%
rename from static/templates/settings/upload-space-stats.handlebars
rename to static/templates/settings/upload_space_stats.hbs
diff --git a/static/templates/settings/user-list-admin.handlebars b/static/templates/settings/user_list_admin.hbs
similarity index 100%
rename from static/templates/settings/user-list-admin.handlebars
rename to static/templates/settings/user_list_admin.hbs
diff --git a/static/templates/settings_tab.handlebars b/static/templates/settings_tab.handlebars
deleted file mode 100644
index d9f41b6cf4..0000000000
--- a/static/templates/settings_tab.handlebars
+++ /dev/null
@@ -1,15 +0,0 @@
-<div id="settings-change-box" class="new-style">
-    {{ partial "settings/account-settings" }}
-
-    {{ partial "settings/display-settings" }}
-
-    {{ partial "settings/notification-settings" }}
-
-    {{ partial "settings/bot-settings" }}
-
-    {{ partial "settings/alert-word-settings" }}
-
-    {{ partial "settings/attachments-settings" }}
-
-    {{ partial "settings/muted-topics-settings" }}
-</div>
diff --git a/static/templates/settings_tab.hbs b/static/templates/settings_tab.hbs
new file mode 100644
index 0000000000..bc6d6e29ae
--- /dev/null
+++ b/static/templates/settings_tab.hbs
@@ -0,0 +1,15 @@
+<div id="settings-change-box" class="new-style">
+    {{ partial "settings/account_settings" }}
+
+    {{ partial "settings/display_settings" }}
+
+    {{ partial "settings/notification_settings" }}
+
+    {{ partial "settings/bot_settings" }}
+
+    {{ partial "settings/alert_word_settings" }}
+
+    {{ partial "settings/attachments_settings" }}
+
+    {{ partial "settings/muted_topics_settings" }}
+</div>
diff --git a/static/templates/sidebar_private_message_list.handlebars b/static/templates/sidebar_private_message_list.hbs
similarity index 100%
rename from static/templates/sidebar_private_message_list.handlebars
rename to static/templates/sidebar_private_message_list.hbs
diff --git a/static/templates/single_message.handlebars b/static/templates/single_message.hbs
similarity index 100%
rename from static/templates/single_message.handlebars
rename to static/templates/single_message.hbs
diff --git a/static/templates/starred_messages_sidebar_actions.handlebars b/static/templates/starred_messages_sidebar_actions.hbs
similarity index 100%
rename from static/templates/starred_messages_sidebar_actions.handlebars
rename to static/templates/starred_messages_sidebar_actions.hbs
diff --git a/static/templates/stream_creation_form.handlebars b/static/templates/stream_creation_form.hbs
similarity index 100%
rename from static/templates/stream_creation_form.handlebars
rename to static/templates/stream_creation_form.hbs
diff --git a/static/templates/stream_member_list_entry.handlebars b/static/templates/stream_member_list_entry.hbs
similarity index 100%
rename from static/templates/stream_member_list_entry.handlebars
rename to static/templates/stream_member_list_entry.hbs
diff --git a/static/templates/stream_privacy.handlebars b/static/templates/stream_privacy.hbs
similarity index 100%
rename from static/templates/stream_privacy.handlebars
rename to static/templates/stream_privacy.hbs
diff --git a/static/templates/stream-settings-checkbox.handlebars b/static/templates/stream_settings_checkbox.hbs
similarity index 100%
rename from static/templates/stream-settings-checkbox.handlebars
rename to static/templates/stream_settings_checkbox.hbs
diff --git a/static/templates/stream_sidebar_actions.handlebars b/static/templates/stream_sidebar_actions.hbs
similarity index 100%
rename from static/templates/stream_sidebar_actions.handlebars
rename to static/templates/stream_sidebar_actions.hbs
diff --git a/static/templates/stream_sidebar_row.handlebars b/static/templates/stream_sidebar_row.hbs
similarity index 100%
rename from static/templates/stream_sidebar_row.handlebars
rename to static/templates/stream_sidebar_row.hbs
diff --git a/static/templates/stream_types.handlebars b/static/templates/stream_types.hbs
similarity index 100%
rename from static/templates/stream_types.handlebars
rename to static/templates/stream_types.hbs
diff --git a/static/templates/subscription.handlebars b/static/templates/subscription.hbs
similarity index 100%
rename from static/templates/subscription.handlebars
rename to static/templates/subscription.hbs
diff --git a/static/templates/subscription_count.handlebars b/static/templates/subscription_count.hbs
similarity index 100%
rename from static/templates/subscription_count.handlebars
rename to static/templates/subscription_count.hbs
diff --git a/static/templates/subscription_invites_warning_modal.handlebars b/static/templates/subscription_invites_warning_modal.hbs
similarity index 100%
rename from static/templates/subscription_invites_warning_modal.handlebars
rename to static/templates/subscription_invites_warning_modal.hbs
diff --git a/static/templates/subscription_members.handlebars b/static/templates/subscription_members.hbs
similarity index 100%
rename from static/templates/subscription_members.handlebars
rename to static/templates/subscription_members.hbs
diff --git a/static/templates/subscription_setting_icon.handlebars b/static/templates/subscription_setting_icon.hbs
similarity index 100%
rename from static/templates/subscription_setting_icon.handlebars
rename to static/templates/subscription_setting_icon.hbs
diff --git a/static/templates/subscription_settings.handlebars b/static/templates/subscription_settings.hbs
similarity index 98%
rename from static/templates/subscription_settings.handlebars
rename to static/templates/subscription_settings.hbs
index 5e331bcf19..0c25158b67 100644
--- a/static/templates/subscription_settings.handlebars
+++ b/static/templates/subscription_settings.hbs
@@ -51,7 +51,7 @@
                 <ul class="grey-box">
                     {{#each settings}}
                     <li>
-                        {{partial "stream-settings-checkbox"
+                        {{partial "stream_settings_checkbox"
                           "setting_name" name
                           "prefix" "sub_"
                           "suffix" "_setting"
diff --git a/static/templates/subscription_stream_privacy_modal.handlebars b/static/templates/subscription_stream_privacy_modal.hbs
similarity index 100%
rename from static/templates/subscription_stream_privacy_modal.handlebars
rename to static/templates/subscription_stream_privacy_modal.hbs
diff --git a/static/templates/subscription_table_body.handlebars b/static/templates/subscription_table_body.hbs
similarity index 100%
rename from static/templates/subscription_table_body.handlebars
rename to static/templates/subscription_table_body.hbs
diff --git a/static/templates/subscription_type.handlebars b/static/templates/subscription_type.hbs
similarity index 100%
rename from static/templates/subscription_type.handlebars
rename to static/templates/subscription_type.hbs
diff --git a/static/templates/subscriptions.handlebars b/static/templates/subscriptions.hbs
similarity index 100%
rename from static/templates/subscriptions.handlebars
rename to static/templates/subscriptions.hbs
diff --git a/static/templates/tab_bar.handlebars b/static/templates/tab_bar.hbs
similarity index 100%
rename from static/templates/tab_bar.handlebars
rename to static/templates/tab_bar.hbs
diff --git a/static/templates/topic_edit_form.handlebars b/static/templates/topic_edit_form.hbs
similarity index 100%
rename from static/templates/topic_edit_form.handlebars
rename to static/templates/topic_edit_form.hbs
diff --git a/static/templates/topic_list_item.handlebars b/static/templates/topic_list_item.hbs
similarity index 100%
rename from static/templates/topic_list_item.handlebars
rename to static/templates/topic_list_item.hbs
diff --git a/static/templates/topic_muted.handlebars b/static/templates/topic_muted.hbs
similarity index 100%
rename from static/templates/topic_muted.handlebars
rename to static/templates/topic_muted.hbs
diff --git a/static/templates/topic_sidebar_actions.handlebars b/static/templates/topic_sidebar_actions.hbs
similarity index 100%
rename from static/templates/topic_sidebar_actions.handlebars
rename to static/templates/topic_sidebar_actions.hbs
diff --git a/static/templates/typeahead_list_item.handlebars b/static/templates/typeahead_list_item.hbs
similarity index 100%
rename from static/templates/typeahead_list_item.handlebars
rename to static/templates/typeahead_list_item.hbs
diff --git a/static/templates/typing_notification.handlebars b/static/templates/typing_notification.hbs
similarity index 100%
rename from static/templates/typing_notification.handlebars
rename to static/templates/typing_notification.hbs
diff --git a/static/templates/typing_notifications.handlebars b/static/templates/typing_notifications.hbs
similarity index 100%
rename from static/templates/typing_notifications.handlebars
rename to static/templates/typing_notifications.hbs
diff --git a/static/templates/unstar-messages-modal.handlebars b/static/templates/unstar_messages_modal.hbs
similarity index 100%
rename from static/templates/unstar-messages-modal.handlebars
rename to static/templates/unstar_messages_modal.hbs
diff --git a/static/templates/uploaded_files_list.handlebars b/static/templates/uploaded_files_list.hbs
similarity index 100%
rename from static/templates/uploaded_files_list.handlebars
rename to static/templates/uploaded_files_list.hbs
diff --git a/static/templates/user_group_info_popover.handlebars b/static/templates/user_group_info_popover.hbs
similarity index 100%
rename from static/templates/user_group_info_popover.handlebars
rename to static/templates/user_group_info_popover.hbs
diff --git a/static/templates/user_group_info_popover_content.handlebars b/static/templates/user_group_info_popover_content.hbs
similarity index 100%
rename from static/templates/user_group_info_popover_content.handlebars
rename to static/templates/user_group_info_popover_content.hbs
diff --git a/static/templates/user-groups-admin.handlebars b/static/templates/user_groups_admin.hbs
similarity index 100%
rename from static/templates/user-groups-admin.handlebars
rename to static/templates/user_groups_admin.hbs
diff --git a/static/templates/user-info-form-modal.handlebars b/static/templates/user_info_form_modal.hbs
similarity index 100%
rename from static/templates/user-info-form-modal.handlebars
rename to static/templates/user_info_form_modal.hbs
diff --git a/static/templates/user_info_popover_content.handlebars b/static/templates/user_info_popover_content.hbs
similarity index 100%
rename from static/templates/user_info_popover_content.handlebars
rename to static/templates/user_info_popover_content.hbs
diff --git a/static/templates/user_info_popover_title.handlebars b/static/templates/user_info_popover_title.hbs
similarity index 100%
rename from static/templates/user_info_popover_title.handlebars
rename to static/templates/user_info_popover_title.hbs
diff --git a/static/templates/user_presence_row.handlebars b/static/templates/user_presence_row.hbs
similarity index 100%
rename from static/templates/user_presence_row.handlebars
rename to static/templates/user_presence_row.hbs
diff --git a/static/templates/user_presence_rows.handlebars b/static/templates/user_presence_rows.hbs
similarity index 100%
rename from static/templates/user_presence_rows.handlebars
rename to static/templates/user_presence_rows.hbs
diff --git a/static/templates/user_profile_modal.handlebars b/static/templates/user_profile_modal.hbs
similarity index 100%
rename from static/templates/user_profile_modal.handlebars
rename to static/templates/user_profile_modal.hbs
diff --git a/static/templates/widgets/poll-widget.handlebars b/static/templates/widgets/poll_widget.hbs
similarity index 100%
rename from static/templates/widgets/poll-widget.handlebars
rename to static/templates/widgets/poll_widget.hbs
diff --git a/static/templates/widgets/poll-widget-results.handlebars b/static/templates/widgets/poll_widget_results.hbs
similarity index 100%
rename from static/templates/widgets/poll-widget-results.handlebars
rename to static/templates/widgets/poll_widget_results.hbs
diff --git a/static/templates/widgets/tictactoe-widget.handlebars b/static/templates/widgets/tictactoe_widget.hbs
similarity index 100%
rename from static/templates/widgets/tictactoe-widget.handlebars
rename to static/templates/widgets/tictactoe_widget.hbs
diff --git a/static/templates/widgets/todo-widget.handlebars b/static/templates/widgets/todo_widget.hbs
similarity index 100%
rename from static/templates/widgets/todo-widget.handlebars
rename to static/templates/widgets/todo_widget.hbs
diff --git a/static/templates/widgets/todo-widget-tasks.handlebars b/static/templates/widgets/todo_widget_tasks.hbs
similarity index 100%
rename from static/templates/widgets/todo-widget-tasks.handlebars
rename to static/templates/widgets/todo_widget_tasks.hbs
diff --git a/static/templates/widgets/zform-choices.handlebars b/static/templates/widgets/zform_choices.hbs
similarity index 100%
rename from static/templates/widgets/zform-choices.handlebars
rename to static/templates/widgets/zform_choices.hbs
diff --git a/tools/check-templates b/tools/check-templates
index ad3cae16e5..72e735280a 100755
--- a/tools/check-templates
+++ b/tools/check-templates
@@ -27,10 +27,10 @@ def check_our_files(modified_only, all_dups, targets):
         lister.list_files(
             targets=targets,
             modified_only=args.modified,
-            ftypes=['handlebars', 'html'],
+            ftypes=['hbs', 'html'],
             group_by_ftype=True, exclude=EXCLUDED_FILES))
 
-    check_handlebar_templates(by_lang['handlebars'])
+    check_handlebar_templates(by_lang['hbs'])
     check_html_templates(by_lang['html'], args.all_dups)
 
 def check_html_templates(templates, all_dups):
@@ -145,11 +145,11 @@ def check_html_templates(templates, all_dups):
 def check_handlebar_templates(templates):
     # type: (Iterable[str]) -> None
     # Check all our handlebars templates.
-    templates = [fn for fn in templates if fn.endswith('.handlebars')]
+    templates = [fn for fn in templates if fn.endswith('.hbs')]
 
     IGNORE_FILES = [
         # TODO: Add some exclude mechanism for the line-wrapping issue here.
-        'static/templates/recipient_row.handlebars',
+        'static/templates/recipient_row.hbs',
     ]
 
     for fn in templates:
diff --git a/tools/html-grep b/tools/html-grep
index 881aa41b9b..92adb24ff6 100755
--- a/tools/html-grep
+++ b/tools/html-grep
@@ -41,7 +41,7 @@ USAGE = '''
     Finding files to search:
 
         The tool currently searches your git repo for files with
-        the extension .html or .handlebars., and then it does
+        the extension .html or .hbs., and then it does
         the grep against all those files.
 
         TODO: allow specific files to be searched.'''
@@ -72,7 +72,7 @@ def check_our_files():
 
     files = lister.list_files(
         modified_only=options.modified,
-        ftypes=['handlebars', 'html'],
+        ftypes=['hbs', 'html'],
     )
 
     fns = [fn for fn in files if ('casperjs' not in fn) and ('puppet/zulip' not in fn)]
diff --git a/tools/lint b/tools/lint
index 65d351a42a..ae99681c2d 100755
--- a/tools/lint
+++ b/tools/lint
@@ -48,7 +48,7 @@ def run():
 
     by_lang = linter_config.list_files(groups={
         'backend': ['py', 'sh', 'pp', 'json', 'md', 'txt', 'text', 'yaml', 'rst'],
-        'frontend': ['js', 'ts', 'css', 'scss', 'handlebars', 'html'],
+        'frontend': ['js', 'ts', 'css', 'scss', 'hbs', 'html'],
     }, exclude=EXCLUDED_FILES)
 
     linter_config.external_linter('add_class', ['tools/find-add-class'], ['js'],
@@ -70,7 +70,7 @@ def run():
                                   fix_arg='--fix',
                                   description="Standard puppet linter"
                                   "(config: tools/linter_lib/exclude.py)")
-    linter_config.external_linter('templates', ['tools/check-templates'], ['handlebars', 'html'],
+    linter_config.external_linter('templates', ['tools/check-templates'], ['hbs', 'html'],
                                   description="Custom linter checks whitespace formatting"
                                   "of HTML templates.")
     linter_config.external_linter('swagger', ['node', 'tools/check-swagger'], ['yaml'],
diff --git a/tools/linter_lib/custom_check.py b/tools/linter_lib/custom_check.py
index d96f031c9c..13f234d451 100644
--- a/tools/linter_lib/custom_check.py
+++ b/tools/linter_lib/custom_check.py
@@ -646,7 +646,7 @@ html_rules = whitespace_rules + prose_style_rules + cast(Rule, [
      'description': "`title` value should be translatable."},
     {'pattern': r'''\Walt=["'][^{"']''',
      'description': "alt argument should be enclosed by _() or it should be an empty string.",
-     'exclude': set(['static/templates/settings/display-settings.handlebars',
+     'exclude': set(['static/templates/settings/display_settings.hbs',
                      'templates/zerver/app/keyboard_shortcuts.html',
                      'templates/zerver/app/markdown_help.html']),
      'good_lines': ['<img src="{{source_url}}" alt="{{ _(name) }}" />', '<img alg="" />'],
@@ -671,12 +671,12 @@ html_rules = whitespace_rules + prose_style_rules + cast(Rule, [
          # 5xx page doesn't have external CSS
          'static/html/5xx.html',
          # Group PMs color is dynamically calculated
-         'static/templates/group_pms.handlebars',
+         'static/templates/group_pms.hbs',
 
          # exclude_pattern above handles color, but have other issues:
-         'static/templates/draft.handlebars',
-         'static/templates/subscription.handlebars',
-         'static/templates/single_message.handlebars',
+         'static/templates/draft.hbs',
+         'static/templates/subscription.hbs',
+         'static/templates/single_message.hbs',
 
          # Old-style email templates need to use inline style
          # attributes; it should be possible to clean these up
@@ -691,11 +691,11 @@ html_rules = whitespace_rules + prose_style_rules + cast(Rule, [
          'templates/zerver/app/navbar.html',
 
          # Needs the width cleaned up; display: none is fine
-         'static/templates/settings/account-settings.handlebars',
+         'static/templates/settings/account_settings.hbs',
 
          # background image property is dynamically generated
-         'static/templates/user_profile_modal.handlebars',
-         'static/templates/sidebar_private_message_list.handlebars',
+         'static/templates/user_profile_modal.hbs',
+         'static/templates/sidebar_private_message_list.hbs',
 
          # Inline styling for an svg; could be moved to CSS files?
          'templates/zerver/landing_nav.html',
@@ -707,8 +707,8 @@ html_rules = whitespace_rules + prose_style_rules + cast(Rule, [
          'templates/corporate/upgrade.html',
 
          # Miscellaneous violations to be cleaned up
-         'static/templates/user_info_popover_title.handlebars',
-         'static/templates/subscription_invites_warning_modal.handlebars',
+         'static/templates/user_info_popover_title.hbs',
+         'static/templates/subscription_invites_warning_modal.hbs',
          'templates/zerver/reset_confirm.html',
          'templates/zerver/config_error.html',
          'templates/zerver/dev_env_email_access_details.html',
@@ -726,7 +726,7 @@ html_rules = whitespace_rules + prose_style_rules + cast(Rule, [
 ])
 
 handlebars_rules = RuleList(
-    langs=['handlebars'],
+    langs=['hbs'],
     rules=html_rules + cast(Rule, [
         {'pattern': "[<]script",
          'description': "Do not use inline <script> tags here; put JavaScript in static/js instead."},
diff --git a/tools/webpack.config.ts b/tools/webpack.config.ts
index 2e171b3271..f1dfee1329 100644
--- a/tools/webpack.config.ts
+++ b/tools/webpack.config.ts
@@ -79,7 +79,7 @@ export default (env?: string): webpack.Configuration[] => {
                     ],
                 },
                 {
-                    test: /\.handlebars$/,
+                    test: /\.hbs$/,
                     loader: 'handlebars-loader',
                     options: {
                         // Tell webpack not to explicitly require these.
diff --git a/zerver/management/commands/makemessages.py b/zerver/management/commands/makemessages.py
index 86bf531a9f..3151d07969 100644
--- a/zerver/management/commands/makemessages.py
+++ b/zerver/management/commands/makemessages.py
@@ -163,7 +163,7 @@ class Command(makemessages.Command):
         dirname = self.get_template_dir()
 
         for dirpath, dirnames, filenames in os.walk(dirname):
-            for filename in [f for f in filenames if f.endswith(".handlebars")]:
+            for filename in [f for f in filenames if f.endswith(".hbs")]:
                 if filename.startswith('.'):
                     continue
                 with open(os.path.join(dirpath, filename), 'r') as reader: