[csswg-drafts] [css-cascade] What is the encapsulation context of the user and user agent style sheets? (#13829)

cdoublev has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-cascade] What is the encapsulation context of the user and user agent style sheets? ==
Should they have one? Or should a normal declaration with no encapsulation context not take precedence over a normal declaration with an encapsulation context?

Browsers do not give precedence to a normal declaration in the user or user agent style sheet over a normal declaration in a shadow tree.

  > When comparing two declarations that are sourced from different encapsulation contexts, then for normal rules the declaration from the outer context wins [...].

I do not think the encapsulation context of the user or user agent style sheet is defined anywhere. I do not know if all declarations *must* have an encapsulation context:

  > A document language can provide for blending declarations sourced from different encapsulation contexts [...].

https://drafts.csswg.org/css-cascade-5/#cascade-context

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/13829 using your GitHub account


-- 
Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config

Received on Monday, 20 April 2026 17:22:57 UTC