Bug 99827

Summary: [Shadow]: improve the performance of @host @-rules
Product: WebKit Reporter: Takashi Sakamoto <tasak>
Component: CSSAssignee: Web Components Team <webcomponents-bugzilla>
Status: RESOLVED CONFIGURATION CHANGED    
Severity: Normal CC: morrita, rniwa
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 97282    

Description Takashi Sakamoto 2012-10-19 03:28:15 PDT 
To check whether any @host @-rules are applied to the given element, currently it is required to traverse shadow roots and to ask StyleScopeResolver about each ShadowRoot.
It would be a little slow. ElementShadow (or suitable class) should have some flag to cache whether any @host @-rules is applied to shadow host or not.
Comment 1 Ryosuke Niwa 2019-10-04 22:34:14 PDT 
@host is no longer a thing.