It doesn't seem desirable that ::-webkit-fdlsfdsfs, body { background:lime } results in a green background.
By any chance, is this WPT? https://wpt.fyi/results/css/selectors/webkit-pseudo-element.html?label=master&label=experimental&aligned=&q=webkit+pseudo
This is conformant to this spec: https://drafts.csswg.org/selectors-4/#compat
Clearly I forgot to leave my sense of logic at the door. Thanks Ahmad and Tim!