fix(fabric): fix Text overflow in ScrollView on first render (macOS)#2880
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On macOS, the _containerView (NSScrollView's documentView) has autoresizingMask set so it fills the visible area before React's first layout pass. However, AppKit's autoresizing corrupts the documentView's frame by adding the NSClipView's size delta to the container's dimensions (e.g., during initial tile or window attachment), inflating it well beyond the correct content size and producing massive horizontal and vertical overflow on first render. The fix adds a layoutSubviews override on macOS that resets the documentView frame to the correct React-managed content size after AppKit's layout pass (which triggers autoresizing). This corrects the corruption while preserving the autoresizingMask needed for the documentView to fill the visible area before React's first updateState. Fixes microsoft#2857 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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…icrosoft#2880) ## Summary - Add a `layoutSubviews` override in `RCTScrollViewComponentView` on macOS that resets the `_containerView` (documentView) frame to `_contentSize` after AppKit's autoresizing corrupts it - This fixes massive horizontal and vertical overflow when Text is nested inside a ScrollView on the first render ## Root Cause On macOS, the `_containerView` serves as the `NSScrollView`'s `documentView`, whose frame **directly determines the scrollable content area** (unlike iOS where `UIScrollView.contentSize` is a separate property). React's layout system explicitly manages `_containerView.frame` via `updateState:` to match the content bounding rect. However, `autoresizingMask` caused AppKit to **also** resize the container whenever the `NSClipView` resized (e.g., during initial `tile` after mounting). This added the clip view's size delta to the container's dimensions, inflating it well beyond the correct content size. The `layoutSubviews` override runs after AppKit's layout pass (which triggers autoresizing), so it reliably corrects the frame back to the React-managed `_contentSize`. The issue self-corrects on window resize because the size change triggers a React re-layout that overwrites the corrupted frame with fresh measurements. ## Test plan | Before (bug) | After (fix) | |---|---| | <img src="https://github.com/user-attachments/assets/6a63357e-6dd3-4f69-b134-2d0f78c5b995" /> | <img src="https://github.com/user-attachments/assets/5678e2ad-bc40-4987-aaa3-5854c809649e" /> | Fixes microsoft#2857 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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## Summary Backport of 3 fixes from `main` to `0.81-stable`: - **fix(fabric):** Switch default Text color to `labelColor` (#2878) - **fix(fabric):** fix Text overflow in ScrollView on first render (#2880) - **fix(fabric):** Add back compat layer for `validKeysDown` and `validKeysUp` (#2879) Each fix is a separate commit for easy rebasing when upstream PRs are updated. ### Conflict resolutions - **PR #2878:** 0.81-stable uses `RCTUIColor` (renamed from `RCTPlatformColor` on main). Resolved by keeping `RCTUIColor` while applying the `blackColor` → `labelColor` change. - **PRs #2880 and #2879** cherry-picked cleanly. #2879 (open PR) was squash-cherry-picked into a single commit. ## Test plan - [ ] Verify default text color respects dark/light mode - [ ] Verify Text in ScrollView renders correctly on first load - [ ] Verify legacy `validKeysDown`/`validKeysUp` props still work in Fabric 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
layoutSubviewsoverride inRCTScrollViewComponentViewon macOS that resets the_containerView(documentView) frame to_contentSizeafter AppKit's autoresizing corrupts itRoot Cause
On macOS, the
_containerViewserves as theNSScrollView'sdocumentView, whose frame directly determines the scrollable content area (unlike iOS whereUIScrollView.contentSizeis a separate property).React's layout system explicitly manages
_containerView.frameviaupdateState:to match the content bounding rect. However,autoresizingMaskcaused AppKit to also resize the container whenever theNSClipViewresized (e.g., during initialtileafter mounting). This added the clip view's size delta to the container's dimensions, inflating it well beyond the correct content size.The
layoutSubviewsoverride runs after AppKit's layout pass (which triggers autoresizing), so it reliably corrects the frame back to the React-managed_contentSize.The issue self-corrects on window resize because the size change triggers a React re-layout that overwrites the corrupted frame with fresh measurements.
Test plan
Fixes #2857
🤖 Generated with Claude Code