Accordion: Text in a closed accordion panel cannot be found via the browser search

Why this is a good first issue

The issue requires adding a browser-supported attribute to fix search functionality in accordion panels.

AI Summary

The issue involves adding the `hidden='until-found'` attribute to accordion panel content to enable browser search functionality. The solution is straightforward but requires ensuring compatibility across major browsers, which is now feasible as Safari has added support.

Issue Description

Description

This issue came up in the WordPress Online Meetup DACH.

Content in a closed accordion panel is cannot be found via the browser search. It does work in the details block, which opens automatically.

It might make sense to add hidden="until-found" attribute: https://developer.chrome.com/docs/css-ui/hidden-until-found

Step-by-step reproduction instructions

Create an accordion and add text to accordion panel
View the post
Open the browser search with cmd+F
Search for a word that is in the text in the panel

Screenshots, screen recording, code snippet

Editor

As you can see, you cannot find the text:

It works in the details block:

Environment info

No response

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

Please confirm which theme type you used for testing.

Block
Classic
Hybrid (e.g. classic with theme.json)
Not sure

GitHub Labels

[Type] Bug[Focus] Accessibility (a11y)[Status] In Progress[Block] Accordion