> I chalked up the "New IE" stuff to annoying little CSS issues

Here, too, Safari is the cause of 2/3rds of the lines of exceptional UI code now that Edge switched to a compatible render engine. Or blocks features altogether. All major browsers settled on doing things a certain way and then you remember that you always need to check Safari and of course they want it another way, so you get to re-do the work and duplicate your code with a comment "//because safari wants x to be done this way". I had less trouble with MSIE6 back in the day, though I can't rule out that I did less fancy things back then.

These things are not like "oops we render it differently by chance", it's conscious choices like not supporting SVG or being able to read file names in JavaScript (can't have javascript-based upload progress bars or local file encryption if you want to keep the filename; need to encrypt on the server and have the server report progress back via another channel).

If Firefox had the marketshare of Safari and was mandatory to support because they were a major platform’s browser devs would be cursing their name too but with a different set of things that aren’t exactly like Chrome.

It really does feel like devs are literally developing against Chrome with not even so much a thought at cross-browser compat or a glance at caniuse and then taking their finished site and then working backwards from there on other browsers cursing the compatibility issues when they could have avoided it entirely had they started with a cross-platform subset of browser features. Just the same as how cross-platform native development works.

Hell someone did all the hard work for you https://github.com/amilajack/eslint-plugin-compat

Then multiply by all the npm packages blindly imported that were developed with the same methodology and I see where the rage comes from.