Merge commit 'c76ae7a5c0d247264afa896f081db9d1fd278711' into glitch-soc/merge-upstream

Conflicts:
- `app/javascript/packs/public.jsx`:
  In glitch-soc, this file was split across the following files:
  - `app/javascript/packs/public.jsx`
  - `app/javascript/core/embed.js`
  - `app/javascript/core/settings.js`
  Update all those files accordingly, as well as the related `theme.yml` files.

app/javascript/core/embed.ts

@@ -0,0 +1,41 @@
+//  This file will be loaded on embed pages, regardless of theme.
+
+import 'packs/public-path';
+import ready from '../mastodon/ready';
+
+interface SetHeightMessage {
+  type: 'setHeight';
+  id: string;
+  height: number;
+}
+
+function isSetHeightMessage(data: unknown): data is SetHeightMessage {
+  if (
+    data &&
+    typeof data === 'object' &&
+    'type' in data &&
+    data.type === 'setHeight'
+  )
+    return true;
+  else return false;
+}
+
+window.addEventListener('message', (e) => {
+  // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition -- typings are not correct, it can be null in very rare cases
+  if (!e.data || !isSetHeightMessage(e.data) || !window.parent) return;
+
+  const data = e.data;
+
+  ready(() => {
+    window.parent.postMessage(
+      {
+        type: 'setHeight',
+        id: data.id,
+        height: document.getElementsByTagName('html')[0].scrollHeight,
+      },
+      '*',
+    );
+  }).catch((e) => {
+    console.error('Error in setHeightMessage postMessage', e);
+  });
+});