#### PR Dependency Tree
* **PR #12848** 👈
This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)
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## Summary by CodeRabbit
- **New Features**
- Introduced a feature flag to enable or disable web container
functionality for code block previews.
- **Improvements**
- Code block HTML previews now support an alternative rendering method
based on the new feature flag, enhancing flexibility.
- **Chores**
- Updated feature flag settings by removing an obsolete flag and adding
the new web container flag.
- **Tests**
- Simplified code block preview tests for faster and more direct
validation of HTML preview content.
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## Summary by CodeRabbit
- **New Features**
- Introduced a preview mode for code blocks, allowing users to toggle between code and rendered previews (e.g., HTML output) directly within the editor.
- Added a preview toggle button to the code block toolbar for supported languages.
- Enabled dynamic rendering of code block previews using a shared WebContainer, allowing live HTML previews in an embedded iframe.
- Added HTML preview support with loading and error states for enhanced user feedback.
- Integrated the preview feature as a view extension provider for seamless framework support.
- **Bug Fixes**
- Improved toolbar layout and button alignment for a cleaner user interface.
- **Tests**
- Added end-to-end tests to verify the new code block preview functionality and language switching behavior.
- **Chores**
- Updated development server configuration to include enhanced security headers.
- Added a new runtime dependency for WebContainer support.
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Peng Xiao