Animation keyframes do not function when placed in a style element in a shadowRoot

• Component: DOM
• Status: RESOLVED DUPLICATE

[Steve Orvell]

Created attachment 157320 [details]
Reduction

If a style element inside a shadowRoot defines an animation via @-webkit-keyframes, the animation does not run when used within the shadowRoot.

However, if a style element inside a shadowRoot refers to an animation in a document style element, the animation does run when used within the shadowRoot.

[Takashi Sakamoto]

As styles in a shadow DOM subtree are treated as "scoped" and all scoped @keyframes are ignored (c.f. bug 72462), @-webkit-keyframes declared in a shadow DOM subtree doesn't work.

c.f. 
StyleResolver.cpp
            // FIXME (BUG 72462): We don't add @keyframe rules of scoped style sheets for the moment.                                                                      
            if (scope)
                continue;
            resolver->addKeyframeStyle(static_cast<StyleRuleKeyframes*>(rule));

and 
<style scoped>: Implement scoped @keyframes
https://bugs.webkit.org/show_bug.cgi?id=72462

Best regards,
Takashi Sakamoto

(In reply to comment #0)
> Created an attachment (id=157320) [details]
> Reduction
> 
> If a style element inside a shadowRoot defines an animation via @-webkit-keyframes, the animation does not run when used within the shadowRoot.
> 
> However, if a style element inside a shadowRoot refers to an animation in a document style element, the animation does run when used within the shadowRoot.

[Dominic Cooney]

What should the semantics here be?

[Takashi Sakamoto]

*** This bug has been marked as a duplicate of bug 72462 ***