React Daily: Compiler Improvements and View Transitions

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Good morning, it's June 5th, 2026. Today we're seeing focused improvements to React's compiler reliability alongside continued expansion of experimental view transition features.

The React compiler saw two important bug fixes that address edge cases developers may have encountered. Pull request 36688 fixes an issue where JSX components starting with underscores or dollar signs were incorrectly treated as host elements rather than components. This means tags like underscore Bar or dollar Foo were being handled like div elements, causing the compiler to skip proper memoization. The fix updates the component detection logic in the build HIR process to properly recognize these naming patterns.

Separately, pull request 36691 addresses using declarations in the compiler's HIR system. This change bails out on using declarations, likely preventing compilation errors when encountering this newer JavaScript syntax. Both fixes target the compiler's ability to correctly parse and optimize modern React code patterns.

On the experimental front, view transitions are gaining more sophisticated animation capabilities. Pull request 36690 introduces parent enter and parent exit props for nested view transition components. This allows descendant elements to animate when an ancestor view transition boundary enters or exits the DOM. The feature is gated behind the enable view transition parent enter exit flag and addresses use cases like animating individual list items when their parent container transitions.

These compiler fixes should reduce unexpected behavior when using non-standard component naming or modern JavaScript syntax. The view transition enhancements continue building toward more complex page transition scenarios, though they remain experimental.

That's your React update for today.