I find Firefox less resource-hungry and with the WebIDE and Code Snippets that don't need to import/export to devtools source snippets it might even be ahead of Chrome.
Not always. As a developer I use the latest stable Firefox, since that's what I can recommend to my users.
The only annoyance I have with the developer console is something they only recently added: you now need to right click in the console and tick "Log request and response bodies" every single time. No about:config option. But aside from that, I never noticed much difference. There are some things I like in Firefox that I missed in Chrome but that's probably because I'm used to Firefox. When I went the other way around, going from Chrome to Firefox after a few months of Chrome usage, Firefox had actually caught up and I didn't need Firebug anymore at all. Never noticed anything missing.
Yes, seems like there could be a pref for that. Filed a bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1064458.
I don't know what's better about them, but yeah I too noticed the crashes.
But that all being said, if ANY developer addon lets me manually edit cookies then I will happily use it. Right now they all only let you delete, not alter, cookies. So it is hard[er] to test your site's security against malformed or malicious cookie issues.
> Firefox's developer tools are terrible even compared to Internet Explorer 10/11
Wow what, care to elaborate? I've attempted to use them once and couldn't do the most basic of tasks, went straight to getfirefox.com. Not sure what I tried to do, probably something network related or maybe css modifying.
Eh? Tampermonkey makes it dead easy to write and run userscripts in Chrome. I've already written them for half a dozen sites I go to that could use a little tweaking.
Chrome is only closed source in the sense that Mozilla's Firefox builds are closed source. It doesn't have any features that are unavailable in Chromium. It ships with proprietary Pepper Flash and EME plugins, but both work fine in Chromium too.
Even the much maligned RLZ tracking used by third party Chrome installs to report the installation referrer to Google is an open-source feature (disabled by default in Chromium and the first party Google Chrome builds)
I don't know what environment you live in, but despite the at least 2/3rd adoption rate of Chrome (note, not Chromium but really Google Chrome) over Firefox there is no hate here at all. It's a choice depending on personal preference, and in my case also for FOSS. It's not like Firefox has already lost, which is how you put it.
In fact I've used Chrome for months when I disagreed with Firefox 4's design. In the end I couldn't stand the way Chrome worked and reverted. Besides FOSS, it really is a preference.
I might agree on the topic of making add-ons, though the last time I looked into that (and quickly gave up) for any browser I was maybe 16, which is now 5 years ago. Userscripts is the way I and everyone I know takes, and there Firefox is better than Chrome as far as I know (Chrome requires some tricks because it only accepts scripts from the store these days).