This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.
Created attachment 1618 [details] Testcase https://drafts.csswg.org/cssom/#extensions-to-the-window-interface [[ If pseudoElt is as an ASCII case-insensitive match for either ':before' or '::before' let obj be the ::before pseudo-element of elt. If pseudoElt is as an ASCII case-insensitive match for either ':after' or '::after' let obj be the ::after pseudo-element of elt. ]] The attached testcase alerts "auto" in Firefox, "50px" in Chrome and Safari, and "" in Opera. What should the behavior be when the pseudoelement doesn't exist?
The terminology section says "In this specification the ::before and ::after pseudo-elements are assumed to exist for all elements even if no box is generated for them." https://drafts.csswg.org/cssom/#terminology But that might not make it clear how it should behave; I'll look into this.