Description

WordPress 6.8 introduces a visual regression in block themes with comment forms. The Core/post-comment-form submit button is now stretched to full width.

This is a regression between 6.7 and 6.8; 6.8 beta 3 nor the Gutenberg plugin (20.4) solve this issue.

This appears to stem from changes made here: #64770
That adds width: 100% to buttons.

Step-by-step reproduction instructions

1. Open Playgrounds with 6.7.x
2. visit a post screen, view the comment form
3. Note the form button is quite small and narrow
4. Switch Playgrounds to 6.8beta and view the same page and button
5. Note the button width is 100%

Screenshots, screen recording, code snippet

WP 6.7.x

WP 6.8 beta

Environment info

Default playgrounds configurations, but with two different Core versions.

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