While I also don’t think that a mouse click handler would be problematic, my recent experience is that more complex apps are more and more often broken under firefox, but still work fine under chrome. E.g. miro boards are unusable under firefox, and it’s absolutely shameful of every company that can’t bother testing it on like 2 browsers.

"that can’t bother testing it on like 2 browsers"

Current browser market share: Chrome 64%, Safari 20%, Edge 5.3%, Samsung Internet 3.5%, Firefox: 2.2%

https://www.similarweb.com/browsers/

It is hard justifying extra effort for those 2.2% marketshare, unless you count in idealism. And most companies are there for profit.

There are only 3 browsers these days pretty much:

Chrome, Safari, Firefox.

It really shouldn’t be hard to test.

Have you ever tested something in mobile browsers?

Also, a quick test is easy. But a quick fix - often not so much. Unless you want to break something else.

Edge and samsung internet are basically the same as chrome, so there are only 3 browsers to check. Especially that most stuff just works fine across the browsers, it’s not like cross-platform across OSs, it really is a bare minimum.

> It is hard justifying extra effort for those 2.2% marketshare, unless you count in idealism. And most companies are there for profit.

To me, this attitude always sounds like a local business owner choosing to randomly kick 1 out of every 45 customers out of his store. Is it really that much time/cost/effort to test one more browser?

"Is it really that much time/cost/effort to test one more browser?"

As someone who has over the years all in all spend months of work on catering to FF, I say yes.

It is not the testing. But the fixing of bugs that costs time. Time most buisnesses apparently rather invest elsewhere.