Version 2.0.2 broke my navigation menus because of CSS sanitizer

[Netzberufler]

Bug Description

I'm a theme developer and have added AMP support to several of my themes. I'm using tap:AMP.setState() to set a toggled-on class for multiple mobile dropdown menus and dropdown search fields.

Example CSS:

.main-navigation ul.menu {
	display: none;
}

.main-navigation.toggled-on > ul.menu {
	display: block;
}

My issue is that the .main-navigation.toggled-on class is missing in the AMP CSS since version 2.0.2 and seems to be removed by the Sanitizer. I guess that happens because the toggled-on class is not actually used by default in the HTML markup, only interactively added later.

Because of the missing class, mobile menus are broken with AMP active.

Expected Behaviour

I would like to manually control the CSS sanitizer so my toggled-on class is included in the AMP CSS. I did not find any filter or action hook, but maybe I missed it.

Steps to reproduce

Example of the implementation used:
https://github.com/ThemeZee/harrison/blob/master/template-parts/header/site-navigation.php
https://github.com/ThemeZee/harrison/blob/master/inc/addons.php#L93

Theme Demo with AMP active: https://preview.themezee.com/harrison/
When inspecting, you can see the toggled-on class is added, but has no effect because it is missing in the CSS.

Additional context

• WordPress version: 5.5.1
• Plugin version: 2.0.2
• AMP plugin template mode: Standard / Traditional

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Acceptance criteria

Implementation brief

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Demo

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[Netzberufler]

Btw not sure if this is really a bug, or if I'm doing things wrong. Any input on how I can solve that is highly appreciated :)

[westonruter]

@Netzberufler Thank you for reporting! You have correctly identified a bug. I've created a fix here: #5403. Can you test to confirm it fixes the issue?

[Netzberufler]

@westonruter Yes everything works fine now. Thanks so much for fixing this so quickly

[westonruter]

Excellent. I also just sent you a follow-up email.