Hey sorry for the late reply! You are right to say that's a horrible way to complete an install. I recently started finding more reports matching yours and filed a bug. It looks like this has been going on for months and is starting to look like a bug caused by El Capitan.

Others have complained that El Capitan is causing the same thing to happen to many other programs: https://discussions.apple.com/thread/7307276

A bug has been filed about this to alert the Firefox devs to see if there's anything we can do on our side. Since I assume Chrome can update fine without causing this crazy scenario.

Follow this bug for updates on when to expect a fix: Bug 1258515 - After Firefox update, Macbook won't shutdown https://bugzil.la/1258515

But if this does happen to you again, there is a command you can enter in the Terminal to kill Firefox without having to power down your mac: sudo killall launchservicesd && sudo killall Dock

That will execute 2 commands consecutively to kill Firefox and get your mac back to normal.

If you need more detailed instructions, read: https://support.mozilla.org/en-US/kb/forum-response-firefox-45-mac-wont-shut-down-bug-1

Thanks, noah_SUMO for this.

Not happy to hear it, but glad I'm not the only one that has experienced this problem - sorry it currently requires a Terminal command to do a basic operation. But further to this - a recent 'upgrade' to 45.0.1 resulted in not only the same behaviour as I originally experienced, but now crashes on a regular basis. Anything more than one tab open seems can initiate a crash - no particular site feature can cause it, it seems. Never been a problem for me with older (pre-40) Firefox. And if I 'close' Firefox, that's one thing, but if I 'reopen' it, I end up with another instance of Firefox in the Dock - and then both won't close or allow my Mac to shut down (as above). Only the hard boot (before I got your Terminal command) would clear the other instance.

I've tried disabling my few Add-Ons, I've tried Refresh - heck, I even did a FULL uninstall of Firefox and rebuilt it from a new download, trying it first with no Add-Ons and then with the few I have. Still the crashes.

Whether its the fault of El Capitan or Mozilla, my faith in my once go-to browser is beginning to seriously be tested. Devs need to get back to basics and look less for added 'features' and more towards app 'stability' - even if that means developing a 'Lite' version of the browser.

No problem! Just wanted to let you know you weren't crazy or the only one seeing this problem.

"Whether its the fault of El Capitan or Mozilla, my faith in my once go-to browser is beginning to seriously be tested. Devs need to get back to basics and look less for added 'features' and more towards app 'stability' - even if that means developing a 'Lite' version of the browser."

I especially agree with this comment of yours.

Also just to confirm, my Terminal command was able to kill the Firefox process that wasn't able to close?

And regarding the crashes, that is pretty horrible. Haven't heard of Firefox crashing just for opening more than one tab before. Disabling the addons, doing a Refresh and a uninstall/install of Firefox were the right steps.

But I am wondering, have you been submitting the crashes? If yes, then you'll have to give us the links to the crash reports. They can be found by typing about:crashes in the url bar then pressing enter. Then click the first 3 links and return to the about:crashes page and paste those urls here. With those urls we can looker deeper into what's causing those crashes and hopefully figure out what's causing them.

Hey, Noah_SUMO -

re: Lite version. I'd be infinitely happier with a blazingly fast Lite browser that can handle tabs - surely the original point of the Add-Ons and Plug-Ins was that it permitted users to 'personalize' their browser to beyond the basics? I mean, the basic internet browser has been around for consumers since, what, 1994? Why does it seem like its beyond the ken of devs now? It seems that this need for 'improvements and features' baked in with each new version is the bugaboo of a lot of (often once great) software and OSs. Having got past the original 'fix the bugs' stage, the product gets more bloated, more power-hungry and less stable as each new version comes out - and becomes more Jabba the Hut, when it used to be a Tribble. Heck, I'd even consider paying (granted, not much) for a Lite browser with a minimum of feldercarb and 3rd Party products built-in, with the ability to personalize beyond that via Add-Ons.

re: using the sudo killall - I haven't had the opportunity to try that yet, if only because I haven't really put a lot of faith (read: used) my Firefox a lot recently since these issues kicked in. I will give it a go next it happens. And it will. Sigh.

re: submitting the crashes - in truth , I have not been sending the crashes in. Initially because I thought they were just an aberration - now I fear its a regular feature. To loosely paraphrase a line from a famous play, " “To crash once may be regarded as a misfortune; to crash constantly looks like carelessness.”

If you submit crash reports, then let us have the Crash IDs for two or three of the recent ones, then as Noah says we may be able to help.

You need to accept submitting the crash reports, then visit about:crashes to get the Crash IDs beginning with bp-

• Mozilla Crash Reporter

Hey MleB1, thanks for getting back to me.

We definitely agree on the need for there to be a lite version of Firefox. I even suggested this idea a few years ago. I called it "Firefox Classic" or "Firefox Basic". :P But I should have filed it as a bug looking back now. And since the devs will inevitably still want to create new features, they should make a new feature/experiments focused version for that. Maybe call it Firefox Infinity? Nah, might just be confusing. Leaving it as just 'Firefox' would be simpler. :)

Re: Crashes - I too know the feeling when encountering many crashes and thinking this is hopeless. Sometimes though these crashes do have traceable causes and can lead to a fix or workaround. So I'd ask the next time you encounter some crashes using Firefox, submit at least the first 3 you get and forget about sending the rest. That should be enough to determine if there's a pattern to your crashes. Most of the time they're all the same crash.

Hopefully we can get you some crash relief. As I understand how these crashes have beaten you into a state of diminished faith/optimism for which I sympathize.

Hey Noah_SUMO & john99 -

Thanks for the replies and, in particular, your positive feedback, Noah_SUMO!

Apologies for the tardiness in replying. In truth - and as per my earlier email - I've rather gone 'off' using Firefox since this latest flurry of missteps. Once my go-to, constant and default browser - since v1 - I've sidelined it - taking it off my Dock - and have instead, installed the most recent Google Chrome. I'm not happy about that - the background pervasiveness of the Alphabet / Google Machine and what it exists for is not something I like to encourage, but I gotta tell you, Chrome launches a whole lot faster, doesn't cause the 'spinning beachball' to appear and, with the exception of the beloved TabMix Plus, has the Add-Ons I need, operating as they should. And, so far, _with no crashes_. Its on my Dock as the default browser now. It doesn't have a lot of additional baked-in 'features' I didn't ask for or use, and maybe that's the point. It works.

I'll keep the sidelined Firefox up-to-date as I remember to do so and live in hope that the Team fixes the issues and - best hope - creates a Firefox Lite sometime soon - hey, if you can do a functioning browser for iOS and Android. But until then...

Thanks again, guys.

We already have a Firefox for Android, and a method of giving a Firefox experience on iOS

• https://www.mozilla.org/firefox/android/
• https://www.mozilla.org/firefox/ios/

John99 said

We already have a Firefox for Android, and a method of giving a Firefox experience on iOS

• https://www.mozilla.org/firefox/android/
• https://www.mozilla.org/firefox/ios/

My point exactly. Reasonably stable, lite versions of the browser exist. Just not for 'real' computers. Sigh.

I'll keep my eyes on Bugzilla for the results on the install / crash bug in the meantime.