If an element is positioned absolute and has a percent width, setting max-width to "none" removes the percent width. See attached url for example.
Created attachment 46562 [details] Rendering in FF Rendering on FF for comparison, illustrating the difference.
I was able to retrieve the test case from Wayback Archives and changed into following JSFiddle: Link - https://jsfiddle.net/vr81wz2p/show I am not able to reproduce following using above in Safari 15.5 on macOS 12.4 and all browsers (Chrome Canary 104 and Firefox Nightly 103) renders it the same and matches with the attached sample of "Rendering in FF" from 2010. I think this got fixed along the lines and can be closed as "RESOLVED CONFIGURATION CHANGED". If I am testing incorrectly, please retest accordingly. Thanks!
Thank you for testing!