CSS sanitizer removes classes with a slash (/)

[sboerrigter]

Bug Description

Classes with slashes (such as .w-1/4) are not included in the CSS output on AMP pages.

Expected Behaviour

If the HTML marktup contains a CSS class with a slash (such as class="w-1/4") the styling for that class should be included in the CSS output.

Steps to reproduce

1. Edit a template file (such as single.php).
2. add a CSS class with a slash (such as <h1 class="w-1/4">Blah...</h1>).
3. add styling for that CSS class (such as .w-1/4 { width: 25%; }) or load Tailwind CSS .
4. Visit the regular version of the page and see that the styling is applied.
5. Visit the AMP version of the page and see that the styling is not applied.

Additional context

• WordPress version: 5.4.2
• Plugin version: 1.5.4
• AMP plugin template mode: Transitional

Classes with slashes is a common practice in the popular Tailwind CSS framework.

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Implementation brief

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Demo

Changelog entry

[pierlon]

This seems to be a duplicate of #4609. We do have a fix for this ( see #4610), which is set to be available in v1.6 of the plugin.

[sboerrigter]

@pierlon thanks for the quick reply and sorry that I didn't see #4609.

I just tried the development version of the plugin and it seems like version 1.6 indeed fixes this issue 😄. I'll wait for that to be released. Thanks!