The CSS3 content property fails to be applied when using string or attr() values (it works with images though). Tested with nightly build r24061 (522.4.1) on Windows XP SP2.
Created attachment 15440 [details] testcase
In CSS 2.1, the 'content' property applies only to :before and :after pseudo-elements. WebKit supports string, URI, counter and attr content on :before and :after.
(In reply to comment #2) > In CSS 2.1 Just ignore what I said :-)
Since CSS3 Generated and Replaced Content Module is still working draft I mark this bug as an enhancement request.
I am unable to reproduce this bug in Safari 15.6 on macOS 12.5 and Image: Success Text: Failure attr(): Failure and it is same across all browsers (Chrome Canary 106 and Firefox Nightly 105). I am going to mark this as "RESOLVED CONFIGURATION CHANGED". Thanks!