fix: found lynx.getJSModule in main-thread.js

[upupming]

Summary by CodeRabbit

• Bug Fixes
  • Added runtime safeguard to restrict event emission in development builds, preventing unintended main-thread bundling when operating in background contexts.

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).
• Changeset added, and when a BREAKING CHANGE occurs, it needs to be clearly marked (or not required).

[changeset-bot]

🦋 Changeset detected

Latest commit: 443cae8

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

This PR includes changesets to release 1 package

Name	Type
@lynx-js/react	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[coderabbitai]

📝 Walkthrough

Walkthrough

Adds a changeset entry and introduces a __BACKGROUND__ runtime guard to the onBackgroundSnapshotInstanceUpdateId event emission in the snapshot manager. The event is now gated by both __DEV__ and __BACKGROUND__ conditions instead of __DEV__ alone, restricting emission to development builds running in the background context.

Changes

Cohort / File(s)	Summary
Changeset Documentation .changeset/afraid-chairs-share.md	Documents patch version bump for @lynx-js/react with note about adding __BACKGROUND__ guard on background snapshot event emission.
Runtime Safeguard packages/react/runtime/src/snapshot.ts	Adds __BACKGROUND__ condition alongside __DEV__ to gate onBackgroundSnapshotInstanceUpdateId event emission in backgroundSnapshotInstanceManager.updateId.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• feat: add onBackgroundSnapshotInstanceUpdateId event for Preact Devtools #1173: Modifies the same backgroundSnapshotInstanceManager.updateId event emission logic that this PR guards with an additional condition.
• refactor(react/runtime): improve cleanup of snapshot instances #1293: Refactors background snapshot instance teardown and manager cleanup in related runtime paths.
• ci(benchmark/react): background setAttribute BatchedValues #1655: Adds __BACKGROUND__-guarded behavior to background snapshot handling in similar runtime contexts.

Suggested labels

framework:React

Suggested reviewers

• HuJean
• Yradex
• hzy

Poem

🐰 A guard upon the event stream,
Where background threads dream,
The rabbit hops with dev's keen sight,
Preventing bundled chaos in the night! 🌙

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Title check	⚠️ Warning	The title mentions 'lynx.getJSModule in main-thread.js', but the actual changes add a BACKGROUND guard to the onBackgroundSnapshotInstanceUpdateId event in a background snapshot manager. The title does not reflect the real primary change.	Update the title to accurately describe the actual change, such as 'fix: add BACKGROUND guard to onBackgroundSnapshotInstanceUpdateId event' or similar to reflect the runtime safeguard addition.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch fix/getJSModule-in-mts

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

📢 Thoughts on this report? Let us know!

[codspeed-hq]

Merging this PR will degrade performance by 6.04%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
❌ 1 regressed benchmark
✅ 70 untouched benchmarks
⏩ 3 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	transform 1000 view elements	47.5 ms	45 ms	+5.48%
❌	basic-performance-text-200	17.8 ms	19 ms	-6.04%

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_{Comparing fix/getJSModule-in-mts (443cae8) with main (ed566f0)}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[relativeci]

Web Explorer

#8138 Bundle Size — 384.5KiB (0%).

443cae8(current) vs 39fdf1a main#8129(baseline)

Bundle metrics   1 change

	Current #8138	Baseline #8129
Initial JS	155.59KiB	155.59KiB
Initial CSS	35.1KiB	35.1KiB
Cache Invalidation	0%	0%
Chunks	8	8
Assets	8	8
Modules	237(-0.42%)	238
Duplicate Modules	16	16
Duplicate Code	2.98%	2.98%
Packages	4	4
Duplicate Packages	0	0

Bundle size by type  no changes

	Current #8138	Baseline #8129
JS	253.55KiB	253.55KiB
Other	95.85KiB	95.85KiB
CSS	35.1KiB	35.1KiB

Bundle analysis report Branch fix/getJSModule-in-mts Project dashboard

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