fix: Ignore invalid CSS that affects the CSS of subsequent blocks

[Arukuen]

fixes #3164

notes

[github-actions]

🤖 Pull request artifacts

file	commit
pr3199-stackable-3199-merge.zip	1aa3a4a

[github-actions]

Try this Pull Request in the WordPress playground: https://playground.wordpress.net/?mode=seamless#{"landingPage":"/wp-admin/post-new.php?post_type=page","preferredVersions":{"php":"latest","wp":"latest"},"steps":[{"step":"login","username":"admin","password":"password"},{"step":"installPlugin","pluginZipFile":{"resource":"url","url":"https://raw.githubusercontent.com/gambitph/Stackable/artifacts/pr3199-stackable-3199-merge.zip"}}]}

[bfintal]

I believe the return '' here stops the css from working (because it stops prepending the necessary CSS selector). I think the better way to fix this is to still continue prepending the necessary CSS selector even if a nested selector is used.

CSS selector nesting is now allowed in the CSS standard, so we should allow it also.

[bfintal]

@andeng1106 we need to check if media queries (and shortcut media queries @media mobile still work

[andeng1106]

Issue is now fixed. I just have one query:

@andeng1106 we need to check if media queries (and shortcut media queries @media mobile still work

@bfintal media queries are still working but shortcut media queries (@media mobile) is not working anymore on frontend since 3.13.1 and older versions

Screen.Recording.2024-06-20.at.11.mp4