Steps to reproduce the problem: 1. Go to http://jsfiddle.net/m_gol/WZrYg/ What is the expected behavior? According to http://www.w3.org/TR/cssom/#resolved-value getComputedStyle should return a computed value of zIndex which is 1 if set explicitely even on disconnected elements. What went wrong? getComputedStyle returned "" for zIndex on a disconnected element. Did this work before? No Blink bug: https://code.google.com/p/chromium/issues/detail?id=304700
Based on comment from related Chrome / Blink bug (which was marked as "Wontfix"), this is web-spec bug and this is related comment: https://bugs.chromium.org/p/chromium/issues/detail?id=304700#c15 I am not sure, what is expected behaviour but all browsers (Safari 15.6 on macOS 12.5, Chrome Canary 106 and Firefox Nightly 104) in this JSfiddle just shows - getComputedStyle(div).zIndex: and nothing but empty void in front of it. I think Web-spec clarification bug can be raised subject to Blink comment but nothing specific to do here IMO, if all browsers agree. (Please ignore my comment - if I am wrong). Thanks!
Yeah, it looks like all browsers align here and have for many years (Firefox has changed its behavior in version 65); I guess it's time to close it as Won't fix.