no issue
- Attempts to resolve a flaky test.
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### <samp>🤖 Generated by Copilot at 1a7d420</samp>
Refactor announcement bar preview test to use a helper function for
checking text in iframes. This improves code quality and readability.
refs https://github.com/TryGhost/Product/issues/3807https://github.com/TryGhost/Product/issues/3806
Added double buffering to iframes in Admin to have smoother transitions when swapping out iframes for preview pages.
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### <samp>🤖 Generated by Copilot at ad2b1a9</samp>
Refactored the announcement bar modal and preview components to use a
custom `IframeBuffering` component for better performance and
simplicity. Extracted the `IframeBuffering` component to a new file and
added some types and functions to support it. Removed some unused code
and cleaned up imports.
refs https://github.com/TryGhost/Product/issues/3807
- Added announcement bar customisation to Admin X
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### <samp>🤖 Generated by Copilot at 91368ce</samp>
This pull request enhances the `AnnouncementBarModal` component to
enable users to customize the announcement bar on their site. It adds
editing and previewing features, as well as API integration and toast
notifications.
