The Chrome devs have been astonishingly good. My experience has repeatably been that if they are given a good bug report, they get it fixed and often fix it really fast. Or they reply with excellent technical reasons why not. Also multiple times I have seen extreme corner-case regressions get magically fixed without me reporting anything!
Edge - always waffle and misdirection in reply to bug reports. I only bother to give them very well documented, repeatable bugs, plus attached repro file, for things I really need fixed. However: I did have one good experience recently because I reported the bug for the Edge beta, on a feature they were actively working on catching up to the other browsers (however they still had poor interaction).
Safari: hopeless. Report a critical bug with excellent repro file, and get no response, and no fix.
No rating for Firefox because I haven't bothered reported any bugs to them in the last few years.
Yeah apparently from people familiar with the deep black hole that is Radar you're supposed to keep submitting bugs, dupes count as a vote or something.
I once reported a chrome issue. Got no attention until I found a different issue I thought was related and commented there, which got the attention of someone competent who realized it was a hardware bug they'd fixed before but had a regression.
Not a security bug, just that a very large number of websites didn't load.
A+ experience with the Chrome team
E with Edge
F with Safari
The Chrome devs have been astonishingly good. My experience has repeatably been that if they are given a good bug report, they get it fixed and often fix it really fast. Or they reply with excellent technical reasons why not. Also multiple times I have seen extreme corner-case regressions get magically fixed without me reporting anything!
Edge - always waffle and misdirection in reply to bug reports. I only bother to give them very well documented, repeatable bugs, plus attached repro file, for things I really need fixed. However: I did have one good experience recently because I reported the bug for the Edge beta, on a feature they were actively working on catching up to the other browsers (however they still had poor interaction).
Safari: hopeless. Report a critical bug with excellent repro file, and get no response, and no fix.
No rating for Firefox because I haven't bothered reported any bugs to them in the last few years.
Edit: this is for non-security related bugs.