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## Summary by CodeRabbit
* Bug Fixes
* Prevents duplicate modal instances and remounts, improving stability
across pages.
* Improves auto-mount reliability with better DOM validation and
recovery from mount errors.
* Enhances cleanup during unmounts to avoid residual artifacts and
intermittent UI issues.
* More robust handling of shadow DOM and problematic DOM structures,
reducing crashes.
* Style
* Adds extra top margin to the OS version controls for improved spacing.
* Tests
* Introduces a comprehensive test suite covering mounting, unmounting,
error recovery, i18n, and global state behaviors.
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