- Fix the UI problems with our CodeMirror integration (Fixed view stability; Fixed a focus bug; Fixed errors caused by diagnostics range exceptions; Fixed linter invalidation--see https://discuss.codemirror.net/t/problem-trying-to-force-linting/5823; Implemented edit-coalescing for performance).
- Introduce an algorithm for applying text edits to an AST. Compared to the GUI1 approach, the new algorithm supports deeper identity-stability for expressions (which is important for subexpression metadata and Y.Js sync), as well as reordered-subtree identification.
- Enable the code editor.