diff --git a/app/assets/javascripts/discourse/app/lib/load-js-diff.js b/app/assets/javascripts/discourse/app/lib/load-js-diff.js
new file mode 100644
index 0000000000000..3be4da6b4aa2d
--- /dev/null
+++ b/app/assets/javascripts/discourse/app/lib/load-js-diff.js
@@ -0,0 +1,7 @@
+/*
+Plugins & themes are unable to async-import npm modules directly.
+This wrapper provides them with a way to use morphlex, while keeping the `import()` in core's codebase.
+*/
+export default async function loadJSDiff() {
+  return await import("diff");
+}
diff --git a/app/assets/javascripts/discourse/package.json b/app/assets/javascripts/discourse/package.json
index fe27e6411329f..78c4769205dcf 100644
--- a/app/assets/javascripts/discourse/package.json
+++ b/app/assets/javascripts/discourse/package.json
@@ -27,6 +27,7 @@
     "@messageformat/runtime": "^3.0.1",
     "ace-builds": "^1.41.0",
     "decorator-transforms": "^2.3.0",
+    "diff": "^8.0.1",
     "discourse-widget-hbs": "workspace:1.0.0",
     "ember-curry-component": "^0.3.0",
     "ember-resolver": "^13.1.1",
@@ -35,6 +36,8 @@
     "highlight.js": "11.11.1",
     "immer": "^10.1.1",
     "jspreadsheet-ce": "^4.15.0",
+    "moment": "2.30.1",
+    "moment-timezone": "0.5.45",
     "morphlex": "^0.0.16",
     "orderedmap": "^2.1.1",
     "pretty-text": "workspace:1.0.0",
@@ -51,9 +54,7 @@
     "prosemirror-schema-list": "^1.5.1",
     "prosemirror-state": "^1.4.3",
     "prosemirror-transform": "^1.10.4",
-    "prosemirror-view": "^1.39.3",
-    "moment": "2.30.1",
-    "moment-timezone": "0.5.45"
+    "prosemirror-view": "^1.39.3"
   },
   "devDependencies": {
     "@babel/core": "^7.27.1",
diff --git a/package.json b/package.json
index fba651b7766ca..b6c95507e474c 100644
--- a/package.json
+++ b/package.json
@@ -84,4 +84,4 @@
       ]
     }
   }
-}
+}
\ No newline at end of file
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index b701a1cb22283..aedd8458bd575 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -284,6 +284,9 @@ importers:
       decorator-transforms:
         specifier: ^2.3.0
         version: 2.3.0(@babel/core@7.27.1)
+      diff:
+        specifier: ^8.0.1
+        version: 8.0.1
       discourse-widget-hbs:
         specifier: workspace:1.0.0
         version: link:../discourse-widget-hbs
@@ -4199,6 +4202,10 @@ packages:
     resolution: {integrity: sha512-PJWHUb1RFevKCwaFA9RlG5tCd+FO5iRh9A8HEtkmBH2Li03iJriB6m6JIN4rGz3K3JLawI7/veA1xzRKP6ISBw==}
     engines: {node: '>=0.3.1'}
 
+  diff@8.0.1:
+    resolution: {integrity: sha512-rEaM3KmVm78zE3dFZaop3aCQa2MTm+T4kcigUFLVU/KbOYdiY6JnL2g2puOYnct3QFw9pjZadaCbCZ1O8ArMlQ==}
+    engines: {node: '>=0.3.1'}
+
   dir-glob@3.0.1:
     resolution: {integrity: sha512-WkrWp9GR4KXfKGYzOLmTuGVi1UWFfws377n9cc55/tb6DuqyF6pcQ5AbiHEshaDpY9v6oaSr2XCDidGmMwdzIA==}
     engines: {node: '>=8'}
@@ -12618,6 +12625,8 @@ snapshots:
 
   diff@7.0.0: {}
 
+  diff@8.0.1: {}
+
   dir-glob@3.0.1:
     dependencies:
       path-type: 4.0.0