Fix TipTap editor mount race (#6779)

## Summary

- wait for TipTap's mount lifecycle before reading the selection
formatting tray's editor DOM
- detach and reattach DOM listeners across editor view unmounts and
remounts
- cover mounted and pre-mount editor view access

## Testing

- `just ci`
- `pnpm build:e2e`
- `pnpm exec playwright test
tests/e2e/composer-selection-formatting.spec.ts --project=smoke --grep
"right-clicking selected composer text"`
- Native Builderlab staging: reproduced the pre-mount crash on main,
relaunched with the fix, and verified the composer mounts without the
TipTap error

Signed-off-by: kenny lopez <klopez4212@gmail.com>

desktop/src/features/messages/ui/SelectionFormattingTray.tsx

@@ -4,6 +4,7 @@ import type { Editor } from "@tiptap/react";
 
 import { cn } from "@/shared/lib/cn";
 import { FormattingToolbar } from "./FormattingToolbar";
+import { getMountedEditorDom } from "./selectionFormattingTrayEditorDom";
 
 type SelectionFormattingTrayProps = {
   editor: Editor | null;
@@ -129,6 +130,7 @@ export function SelectionFormattingTray({
     if (
       suppressRightClickUpdatesRef.current ||
       !editor ||
+      !getMountedEditorDom(editor) ||
       disabled ||
       !editor.isEditable ||
       !editor.isFocused
@@ -161,7 +163,7 @@ export function SelectionFormattingTray({
       return;
     }
 
-    const editorDom = editor.view.dom;
+    let editorDom: HTMLElement | null = null;
     const hide = () => setPosition(null);
     const handleContextMenu = () => {
       suppressRightClickUpdatesRef.current = true;
@@ -176,26 +178,44 @@ export function SelectionFormattingTray({
       if (event.button === 0) clearSuppression();
     };
 
-    scheduleUpdate();
+    const detachEditorDom = () => {
+      if (!editorDom) return;
+      editorDom.removeEventListener("contextmenu", handleContextMenu);
+      editorDom.removeEventListener("pointerdown", handlePointerDown);
+      editorDom.removeEventListener("keydown", clearSuppression);
+      editorDom = null;
+    };
+
+    const attachEditorDom = () => {
+      const nextEditorDom = getMountedEditorDom(editor);
+      if (!nextEditorDom || nextEditorDom === editorDom) return;
+      detachEditorDom();
+      editorDom = nextEditorDom;
+      editorDom.addEventListener("contextmenu", handleContextMenu);
+      editorDom.addEventListener("pointerdown", handlePointerDown);
+      editorDom.addEventListener("keydown", clearSuppression);
+      scheduleUpdate();
+    };
+
+    editor.on("mount", attachEditorDom);
+    editor.on("unmount", detachEditorDom);
     editor.on("selectionUpdate", scheduleUpdate);
     editor.on("transaction", scheduleUpdate);
     editor.on("focus", scheduleUpdate);
     editor.on("blur", hide);
-    editorDom.addEventListener("contextmenu", handleContextMenu);
-    editorDom.addEventListener("pointerdown", handlePointerDown);
-    editorDom.addEventListener("keydown", clearSuppression);
     window.addEventListener("resize", scheduleUpdate);
     window.addEventListener("scroll", scheduleUpdate, true);
+    attachEditorDom();
 
     return () => {
       cancelScheduledUpdate();
+      editor.off("mount", attachEditorDom);
+      editor.off("unmount", detachEditorDom);
       editor.off("selectionUpdate", scheduleUpdate);
       editor.off("transaction", scheduleUpdate);
       editor.off("focus", scheduleUpdate);
       editor.off("blur", hide);
-      editorDom.removeEventListener("contextmenu", handleContextMenu);
-      editorDom.removeEventListener("pointerdown", handlePointerDown);
-      editorDom.removeEventListener("keydown", clearSuppression);
+      detachEditorDom();
       window.removeEventListener("resize", scheduleUpdate);
       window.removeEventListener("scroll", scheduleUpdate, true);
     };

desktop/src/features/messages/ui/selectionFormattingTrayEditorDom.test.mjs

@@ -0,0 +1,28 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import { getMountedEditorDom } from "./selectionFormattingTrayEditorDom.ts";
+
+test("returns null while the TipTap editor view is not mounted", () => {
+  const editor = {
+    get view() {
+      return new Proxy(
+        {},
+        {
+          get(_target, key) {
+            throw new Error(`editor view cannot access ${String(key)}`);
+          },
+        },
+      );
+    },
+  };
+
+  assert.equal(getMountedEditorDom(editor), null);
+});
+
+test("returns the editor DOM after the TipTap view mounts", () => {
+  const dom = {};
+  const editor = { view: { dom } };
+
+  assert.equal(getMountedEditorDom(editor), dom);
+});

desktop/src/features/messages/ui/selectionFormattingTrayEditorDom.ts

@@ -0,0 +1,10 @@
+import type { Editor } from "@tiptap/react";
+
+/** Returns the editor DOM only after TipTap has mounted its view. */
+export function getMountedEditorDom(editor: Editor): HTMLElement | null {
+  try {
+    return editor.view.dom;
+  } catch {
+    return null;
+  }
+}