Emilio Cobos Álvarezunread,
Feb 22, 2021, 6:42:15 AM2/22/21
No other browser supports anything like this, and we don't even have
internal uses of this pseudo-class.
Only uses of this I've found on the wild were just resetting the box
shadow internal styling we added in bug 582277 (and since removed in bug
I plan to put this behind a (default-off) pref in bug 1694129, but let
me know if there's any objection to this.