Use native auto sizes in Firefox 150+

[stefan-burke]

Summary

• skip the autosizes shim in Firefox 150 and newer
• retain the shim for Safari and older Firefox releases
• cover the Firefox support boundary and Safari behavior

Testing

• bun test
• bun run build
• pre-commit checks

Summary by CodeRabbit

• Bug Fixes

  • Improved autosizing support detection across Chrome and Firefox versions.
  • Ensured the autosizing polyfill runs appropriately in Safari and older Firefox releases.

• Tests

  • Expanded browser compatibility coverage for autosizing behavior.
  • Maintained image filtering coverage for local images with relative paths.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: 9fb6686f-e8ab-4c1e-8d31-a9e87fa9dd03

📥 Commits

Reviewing files that changed from the base of the PR and between 649d338 and b3695ad.

📒 Files selected for processing (3)

• src/_lib/public/ui/autosizes.js
• test/code-quality/code-quality-exceptions.js
• test/unit/build/autosizes.test.js

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📝 Walkthrough

Walkthrough

The autosizes polyfill browser detection now uses Chrome and Firefox version thresholds. Tests cover Firefox 149/150 behavior and Safari fallback, with a relocated code-quality exception and a formatting-only image test update.

Changes

Autosizes browser detection

Layer / File(s)	Summary
Browser version detection src/_lib/public/ui/autosizes.js	Chrome versions below 126 and Firefox versions below 150 use the polyfill; unrecognized browsers default to polyfill usage.
Detection tests and maintenance test/unit/build/autosizes.test.js, test/code-quality/code-quality-exceptions.js	Tests verify Firefox thresholds and Safari behavior, the nullish-coalescing exception location is updated, and image attributes are reformatted without behavioral changes.

Estimated code review effort: 3 (Moderate) | ~20 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly reflects the main change: native auto sizes in Firefox 150+ instead of the shim.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch firefox-native-auto-sizes

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