Probably because "you have to support it". If it does not work out of the box, but does work in Chrome, noone is going to bother to fix it. Same thing happened to IE - required additional code in order to work, and devs ignored it unless requested to do so.

So if FF made sure that everything is matching 1:1 (css, js), then it should just work... But sometimes as each browser decides to implement same thing using different naming.. Things break.

As a primarily Firefox dev, in my experience, sticking to standard web technology, all I build in FF will 99% of the time work in chrome. So if building in Chrome will often not work in Firefox, this rather seems to be the developers fault? I get the impression, Chrome today is rather like the time of IE, where developers used a bunch of non-standard features (or in chromes case maybe to new ones) that then make the page unusable in other browsers.

I get that putting extra work in for special browsers is not great, but these days it should be not more work than using some vendor prefixes for css rules. If your page works in chrome but not Firefox, I would suspect it also wont work in edge, safari or opera. And that's on you as a developer, not on these browsers.

I have Firefox and Firefox Developer Edition installed on my machine, though my primary workhorse is Chrome Canary(i trade privacy for efficiency and experience). First of all playing video in Firefox is jittery and I could hear fans spinning - I don't have any problems in Chrome or Safari. Rust is Mozilla invented language and they are not using it in Firefox for their advantage.

From Safari I expect you're on a Mac. In that case either wait for release 70 or install beta. (And possibly enable webrender as well) The difference is massive in both cpu and energy usage.

Mozilla is certainly using Rust in Firefox. Servo is written in Rust and more and more components from it are getting plugged into Firefox (Quantum CSS comes to mind).

check out ungoogled chromium if you'd like to trade a very small amount of convenience for full privacy

I have never heard of not supporting Firefox until my current corporate position. It astounded me when I heard it would take up to two weeks to get approval and installation of Firefox on my local machine. I wound up getting it, but it noticeably pushed back delivery on some bug fixes. Apparently IE is just more important..

Yes, developers seem to have something against FF, now that chrome is in town.

We're living in the IE-is-the-only-browser age all over again. Only this time in not IE, but Chrome

Definitely, most humans DO NOT LEARN anything with history!!!

They keep making the same mistakes over and over and over...

Very sad...

FF has been the most enterprise hating browser there ever was. They make deployment difficult and for many years were against group policies and msi files. Only recently, after they have lost significant share, have they marginally softened on that stance. To this day, it still takes a third party (FrontMotion) to create deployment msi files.Documentation is often wrong, and one has to suss out how to set certain settings.

On the hand, look at Chrome. Google packages msi files, up to date documentation and group policy admin templates in one download for enterprises. It's no contest. The hell with FF.

We serve large websites in countries where Firefox usage is <0.5% of the total traffic. As long as the website is not utterly broken, it's hard to make a good case for fixing it.

However, we do run all our UI tests against Firefox, Chrome and Safari. Firefox just gets a little less love.

MIDIAccess [1] is not supported

[1] https://developer.mozilla.org/en-US/docs/Web/API/MIDIAccess

If you stick to standards, it should work on Firefox. How nice it would be if some other browsers also played by the rules coughchromecough

We do, but usage statistics is only around 3%

I agree. I use FF almost exclusively on every system I use, both at home and at work. Other browsers are only for testing whether my web stuff works acceptably in their twisted environs, more or less. Whenever I mention anything related to this to my boss, he replies with some sort of (knowledgeable to the point of dangerosity) glib comment like "Chrome! It's the Future!". If that's the future, I want none of it.