diff --git a/web/src/playground_links_popover.ts b/web/src/playground_links_popover.ts
index 7407c2bd3e..dd52f95aaa 100644
--- a/web/src/playground_links_popover.ts
+++ b/web/src/playground_links_popover.ts
@@ -98,9 +98,11 @@ function register_click_handlers(): void {
             const $view_in_playground_button = $(this);
             const $codehilite_div = $(this).closest(".codehilite");
             e.stopPropagation();
-            const playground_info = realm_playground.get_playground_info_for_languages(
-                $codehilite_div.data("code-language"),
-            );
+            const language = $codehilite_div.attr("data-code-language");
+            if (language === undefined) {
+                return;
+            }
+            const playground_info = realm_playground.get_playground_info_for_languages(language);
             if (playground_info === undefined) {
                 return;
             }
diff --git a/web/src/rendered_markdown.ts b/web/src/rendered_markdown.ts
index 898651fedb..b2c250bca4 100644
--- a/web/src/rendered_markdown.ts
+++ b/web/src/rendered_markdown.ts
@@ -278,7 +278,7 @@ export const update_elements = ($content: JQuery): void => {
     $content.find("div.codehilite").each(function (): void {
         const $codehilite = $(this);
         const $pre = $codehilite.find("pre");
-        const fenced_code_lang = $codehilite.data("code-language");
+        const fenced_code_lang = $codehilite.attr("data-code-language");
         let playground_info;
         if (fenced_code_lang !== undefined) {
             playground_info = realm_playground.get_playground_info_for_languages(fenced_code_lang);
diff --git a/web/tests/rendered_markdown.test.js b/web/tests/rendered_markdown.test.js
index ee080f10bc..68d55c3982 100644
--- a/web/tests/rendered_markdown.test.js
+++ b/web/tests/rendered_markdown.test.js
@@ -547,7 +547,7 @@ function test_code_playground(mock_template, viewing_code) {
     $content.set_find_results("div.codehilite", $array([$hilite]));
     $hilite.set_find_results("pre", $pre);
 
-    $hilite.data("code-language", "javascript");
+    $hilite.attr("data-code-language", "javascript");
 
     const $code_buttons_container = $.create("code_buttons_container", {
         children: ["copy-code-stub", "view-code-stub"],