Hi there 👋

Explanations

We wanted to use the following CSS attribute, but the CSS Validator API is not allowing it, resulting in not adding it to the CSS Stylesheet.
I am talking about the aspect-ratio property.
Also note that:

• It is fully accepted in CAN I USE: https://caniuse.com/?search=aspect-ratio
• The online CSS validator accepts it: http://jigsaw.w3.org/css-validator/validator

Steps to reproduce the behaviour:

1. Add the aspect-ratio property on the customizer (additional CSS) or remote css.
2. Even if the property is acceptable, it is wrapped out from the final CSS Stylesheet.

WordCamp

This is related to the WordCamp Genève 2022:

• link to the customizer: https://geneve.wordcamp.org/2022/wp-admin/customize.php?return=%2F2022%2Fwp-admin%2Frevision.php%3Frevision%3D5726
• link to the distant CSS: https://github.com/WPSwitzerland/wordcampgeneve2022/blob/main/assets/css/app.css#L387
• link to the website: https://geneve.wordcamp.org/2022/

Screenshots

Some screenshots:

• Distant CSS with the property:
  

• Customizer CSS with the property:
  

• As a result, in frontend side, the property has been deleted:
  

Many thanks for your help and input.