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applyDelayedPlugins reconfigures ProseMirror's plugin list once its lazily-loaded chunks resolve. Because the plugins array gets a new identity, ProseMirror destroys and recreates every plugin view - including y-prosemirror's cursor plugin, whose destroy handler unconditionally nulls the local awareness 'cursor' field. A user editing before that resolves had their collab cursor silently wiped until their next selection change. Dispatch a no-op transaction right after reconfiguring to force the recreated plugin views through an update pass. Also fixes the flaky multi-window collab e2e test: pins hasFocus() on both pages so cursor broadcast isn't gated on which page/tab holds real browser focus, and replaces flat timeouts with a deterministic wait (plus bounded retry) on the actual yjs awareness state. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Playwright/CDP occasionally drops a single keypress in a run of
keyboard.press('ArrowLeft'/'ArrowRight') calls, leaving the cursor off
by one before the code-mark backticks get typed - producing flaky
failures unrelated to the collab cursor bug (reproduces on main too).
Verify the cursor actually landed where expected via ProseMirror's own
selection state after each movement loop, and press the same key again
to close the gap if a keypress got dropped, instead of trusting the
count blindly.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
mhaack
reviewed
Aug 12, 2026
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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Summary
blocks/edit/prose/index.js:applyDelayedPluginsreconfigures ProseMirror's plugin list once lazily-loaded chunks resolve, which gives the plugins array a new identity and makes ProseMirror destroy+recreate every plugin view — including y-prosemirror's cursor plugin, whose destroy handler unconditionally nulls the local awarenesscursorfield. A user editing before that promise resolves had their collab cursor silently wiped until their next selection change. Fixed by dispatching a no-op transaction right afterupdateStateto force the recreated plugin views through an update pass.Collab cursors in multiple editorse2e test: pinshasFocus()on both pages so cursor broadcast isn't gated on which page/tab holds real browser focus (only one can at a time), and replaces flat timeouts with deterministic waits (plus a bounded retry) on the actual yjs awareness state.edit.spec.js's "Add code mark" test (reproduces onmaintoo, confirmed not caused by the above): Playwright/CDP occasionally drops a single keypress in a run of countedArrowLeft/ArrowRightpresses, leaving the cursor off by one before the code-mark backticks get typed (code→ode). Now verifies the cursor actually landed where expected via ProseMirror's own selection state, and presses the same key again to close the gap if one got dropped.Test plan
edit.spec.jssuite 9+ times locally; consistently passing after the arrow-key drift fix (previously flaky ~1-in-3 runs)npx eslintclean on all changed files🤖 Generated with Claude Code