Description

Whether it is @font-face or @property, an intersection of confusing spec'ing and partial implementation leaves a number of nice capabilities out of reach of shadow root users. Placing @font-face or @property within shadow roots is ignored in some browsers degrading the experience of pre-packaged web components cross browser. This is an area where WPT could also be leveraged to support not falling into this same trap with other and future @ sigil based CSS APIs.

@font-face

• FF bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1077396
• Chrome bug: https://bugs.chromium.org/p/chromium/issues/detail?id=336876

@Property

• Chrome bug: https://bugs.chromium.org/p/chromium/issues/detail?id=1231135

Rationale

The code needed to packages a custom element for reuse should be usage within the custom element package.

Specification

w3c/csswg-drafts#1995

Tests

No response