Revert "Revert "Revert "Improve PageLayout pane drag performance with pointer capture and GPU-accelerated transforms"""

[llastflowers]

Reverts #7275 while some changes are made to better integrate with github-ui.

[changeset-bot]

🦋 Changeset detected

Latest commit: 49f8ccc

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/react	Patch

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[github-actions]

👋 Hi, this pull request contains changes to the source code that github/github-ui depends on. If you are GitHub staff, test these changes with github/github-ui using the integration workflow. Or, apply the integration-tests: skipped manually label to skip these checks.

[primer-integration]

👋 Hi from github/github-ui! Your integration PR is ready: https://github.com/github/github-ui/pull/8660

[Copilot]

Pull request overview

This PR reverts performance optimizations for PageLayout pane dragging, reverting back to a React state-based approach from the previous pointer capture and GPU-accelerated implementation. The change affects drag event handling, ARIA attribute management, CSS optimizations, and removes performance testing infrastructure.

Key Changes:

• Replaced pointer events with mouse events and window-level event listeners for drag handling
• Changed from direct DOM manipulation to React state updates for width and ARIA attributes
• Removed CSS containment and GPU acceleration optimizations during drag operations
• Deleted performance testing stories and removed related e2e test exclusions

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 15 comments.

Show a summary per file

File	Description
packages/react/src/PageLayout/PageLayout.tsx	Reverted drag implementation from pointer capture to mouse events with React state; removed viewport width tracking; changed ARIA attribute handling from DOM manipulation to React props
packages/react/src/PageLayout/PageLayout.module.css	Removed CSS containment and GPU acceleration optimizations; changed to global body-level cursor/selection styles during drag
packages/react/src/PageLayout/__snapshots__/PageLayout.test.tsx.snap	Updated snapshots to show --pane-width now rendered in inline styles for all panes
packages/react/src/PageLayout/PageLayout.performance.stories.tsx	Deleted entire performance testing story file with drag, keyboard, ARIA, and responsive tests
e2e/components/Axe.test.ts	Removed skip entries for deleted performance test stories

Comments suppressed due to low confidence (1)

packages/react/src/PageLayout/PageLayout.performance.stories.tsx:1

• The deletion of PageLayout.performance.stories.tsx removes test coverage for drag performance, keyboard interactions, ARIA attributes, and responsive constraints. While these were Storybook stories rather than automated tests, they provided important manual testing capabilities and documentation for the drag/resize functionality. Consider adding automated tests (unit or e2e) for the drag functionality to ensure it works correctly, especially given the significant implementation changes in this PR.

[primer-integration]

🔬 github-ui Integration Test Results

Check	Status	Details
CI	✅ Passed	View run
Projects (Memex)	⏳ Pending	Waiting for workflow to complete
VRT	✅ Passed	View run

[llastflowers]

Integration tests are passing but not reporting correctly to this PR 🤔 Skipping manually