pierrejeambrun opened a new pull request, #69912: URL: https://github.com/apache/airflow/pull/69912
Every cell in the Dag Grid view subscribed to a shared hover context, so hovering any cell changed the context value and re-rendered the entire grid — the interaction lag reported in #69531, which worsens as the Dag grows. This moves the run-column / task-row crosshair highlight to a single delegated `pointerover` handler that toggles CSS classes on the matching cells by `data-run-id`/`data-task-id`, so hovering does no React render work; the same delegated root covers the gantt so the shared row highlight stays in sync. Measured on a ~20-run × 20-task grid (React Profiler): commits per hover dropped from **~3.0 to ~0.07** — hovering now does essentially zero React work. Appearance is unchanged (same crosshair highlight; selected cells still win). The separate stream-driven full-grid re-render (the other cause of grid slowness in #69531) is addressed in a stacked follow-up on top of this branch. related: #69531 --- ##### Was generative AI tooling used to co-author this PR? - [X] Yes — Claude Code (Opus 4.8) Generated-by: Claude Code (Opus 4.8) following [the guidelines](https://github.com/apache/airflow/blob/main/contributing-docs/05_pull_requests.rst#gen-ai-assisted-contributions) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
