A moderator (AliceWyman, whom I thank for her post) suggests I reset Firefox. I've done that, more than once.

The problem remains. And so does my question : why does Firefox keep on hanging/freezing ?

Why should fixes be necessary? Mozilla, in its Firefox page, generously offers the browser free, and users assume that it will, simply, work. In my case, it doesn't.

And as I've said: I've tried a whole range of fixes and workarounds (that aren't necessary with other browsers) and they haven't worked. If my iMac can handle all the other browsers with no problem, this indicates that the computer works, and that the other browsers do too. So this problem seems to be a specific Firefox one.

As I've already said, I could just give up and use Safari, Chrome, Chromium, SeaMonkey, Maxthon, or Slimboat, for instance.

But it irks me that FF, with such a good reputation (it's the third most widely used browser), should behave in this way.

"Different by design", says its webpage. Well, it's certainly different. Can anyone help? I've been asking these questions, trying "fixes", trashing and clean-reinstalling for about a week now.

I read through this thread and it doesn't look as though you were successful in creating a new Firefox profile - is that right? Have you tried to Reset Firefox? See the Refresh Firefox - reset add-ons and settings article for details.. See Firefox hangs or is not responding - How to fix for other suggestions.

Another way to create a new default profile is to delete the Firefox folder located in your user home directory ~/Library/Application Support folder. Note that the user Library folder is hidden on Mac OS X 10.9. To open it, click the Finder icon in the dock. On the menu bar, click the Go menu, hold down the option or alt key and select Library. A window will open containing your Library folder. (More info here.)

You said earlier, Every time I have tried a new version of Firefox and trashed it I have been careful to trash the associated files too (using an application called Appclean) and performed a clean reinstall. I've been doing this for several years.

I would be careful using any third-party applications to uninstall Firefox. All you should need to do is to move the Firefox.app from the Applications folder to the trash. To start completely fresh, you could also delete (or rename) the "Firefox" folder located in the ~/Library/Application Support folder. This removes all Firefox user data and settings, including passwords and the places.sqlite file (which saves your bookmarks and browsing history and sometimes causes hangs).

Hi AliceWyman

Thanks for your post. Yes, I have been unsuccessful in creating a new profile. I don't mind trying your method (and I will try it), but that shouldn't be necessary: I've trashed and reinstalled F 25 three times since I downloaded it: surely I've had a new profile each time?

As for the "Firefox hangs or is not responding - How to fix"page, believe me, I've tried each solution there, including the one that calls for the use of the Terminal ( and which results in the message "no such file or directory").

Thank you for your suggestions, nonetheless.

Deleted the profile as you suggested. No joy.

However : after trying various permutations I have gone, once more, to the Firefox Add-ons. In the Plug-ins page, where I'd been several times before, I tried a new variation on the number of plug-ins I was disabling.

For the moment, since I did this, Firefox has been running well. I have no idea why, because I don't really know what I've done, and it might not last. Fingers crossed. And (as I've said before) I don't see why it should be necessary.

But I thought of taking a screen shot, which I enclose.

You asked, I've trashed and reinstalled F 25 three times since I downloaded it: surely I've had a new profile each time?

I don't have any idea what that application called Appclean does, if you used it to remove Firefox. Uninstalling Firefox the "normal way (trashing the app) doesn't touch your Firefox profile. See Uninstall Firefox from your computer.

Firefox hangs or is not responding - How to fix does suggest troubleshooting plugins as one of the first steps under the "Firefox hangs at random times" section, which links to Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems.

I would leave your plugins disabled for awhile to make sure the problem does not come back. If the problem does not return with just the Java Applet plugin , Shockwave Flash, and Silverlight plugin disabled (which is what I see in your screenshot), one of them is the likely cause. You can figure out which one is the problem by re-enabling them one at a time.

Thanks ! I don't know which of the plug-ins may have caused the problem, or if my browsing experience - with FF or other browsers- will in any way be affected by disabling them.

I don't even know if the solution will last. But there's only one way of finding out, and that is to carry on as usual and see.

Thanks for your suggestions.

As for Appcleaner (and not Appclean, as I mistakenly called it ), it's freeware. The website explains that it " allows you to safely uninstall apps while keeping the registry intact. Appcleaner will clean your registry, help you to get rid of programs, delete non working apps, clear space and boost your Mac performance! AppCleaner works great with both PC and Mac, is easy to use and also totally free "

I find it invaluable. It saves a lot of time.

If you leave Shockwave Flash, Java, and Silverlight disabled (or if you have ALL plugins disabled, which is the better plugin troubleshooting method) and Firefox continues to work without hangups for a good long test period:

You will probably want to re-activate the Shockwave Flash plugin first, and leave all the other plugins disabled. Flash is needed for so many websites. Java is used less often, and Silverlight less then that.

If Flash turns out to be the problem and keeping it disabled in Firefox isn't an option, see Flash Plugin - Keep it up to date and troubleshoot problems ... but we may be getting ahead of ourselves.

By the way: Setting plugins to "Never Activate" in the Firefox Add-ons Plugins list only disables them in Firefox. Other browsers are not affected.

On AppCleaner: I found http://mac.filehorse.com/download-appcleaner/screenshots/#screenshot5 - I see that, for Chrome, it does offer to remove the ~/Library/Application Support/Chrome folder. For Firefox, then, I'd assume it also offers to remove the ~/Library/Application Support/Firefox folder, which would remove the Firefox profile.

For the moment I'll leave all the plug-ins disabled. And Shockwave isn't compatible with the latest Mac OS ( 10.9 ). But Shockwave did work with previous Mac operating systems, and the Firefox problem dates back about four years (and countless unsuccessful upgrades). Anyhow: now FF seems to be working, I'll stick to that configuration. Let's hope it lasts - I've made a note of the fix for any future versions. Let's also hope it doesn't impair the browsing experience.

Appcleaner does indeed offer to remove the profile. As I've said earlier, I've been performing clean reinstalls thanks to that useful piece of software, and had a new profile every time.

You said, And Shockwave isn't compatible with the latest Mac OS ( 10.9 ).

Adobe's Flash Player (which appears as "Shockwave Flash in your plugins list) should work on OS X 10.9 Mavericks and Firefox according to http://helpx.adobe.com/flash-player/kb/installation-problems-flash-player-mac.html and http://www.adobe.com/products/flashplayer/tech-specs.html

Adobe Flash (formerly Macromedia Flash), refers to the Flash Player and browser plugin needed to handle SWF videos, web page animations and interactive content. Even though the Flash plugin is also referred to as "Shockwave Flash", it should not be confused with the Shockwave plugin that handles "Shockwave for Director" content. 
Ref: http://kb.mozillazine.org/Flash

Hi there, I've ever checked the "override automatic cache management" recently and changed its value to the max. 1024MB. Forgot to change it back to default value and since then my entire Mac Book Air froze from time to time.

I thought of that just now and quickly switched it back to default. Observing the result in coming few days.

- Ray.

• I didn't finish reading the whole long thread above. If my message doesn't help in anyways please ignore heh. Thanks.

xkreiss,

You posted over a month ago, on 11/9/13

Quote:
For the moment I'll leave all the plug-ins disabled. <snip> Anyhow: now FF seems to be working, I'll stick to that configuration. Let's hope it lasts 

Is your issue with Firefox freezes now resolved? If disabling all plugins led to the resolution, which plugin was the problem?

Thanks for your email. Firefox seems to be working now I've disabled Shockwave Flash and Silverlight.

Is my issue with Firefox resolved ? Yes, insofar as I can now use Firefox for the first time in years. No, if you bear in mind that it's the only browser that ever presented these problems. Something that only works with a "fix" is not really satisfactory. And I yet have to see if the disabling of these two plug-ins

However, as I said, the constant hanging/freezes seem to have gone, and I thank you and others for the support.

I had the same problem and it got so annoying that I began using Safari and Chrome, even though I prefer Firefox. Here is how I solved it. I checked tools/add-ons (per the advice on another forum) and discovered that a plug-in for Silverlight needed to be updated or else Firefox would become unstable--which I did. After I did the update, the freezes went away.

lproyect, Thanks for the information, that you solved a similar issue by updating your Silverlight plugin.

xkreiss, Did you ever find out the root cause of the problem? In your last post on Dec 13, 2013 you wrote:

Thanks for your email. Firefox seems to be working now I've disabled Shockwave Flash and Silverlight.

Is my issue with Firefox resolved ? Yes, insofar as I can now use Firefox for the first time in years. No, if you bear in mind that it's the only browser that ever presented these problems. Something that only works with a "fix" is not really satisfactory. And I yet have to see if the disabling of these two plug-ins

However, as I said, the constant hanging/freezes seem to have gone, and I thank you and others for the support.

I'm going to mark your Dec 13, 2013 post as the "solution", for now.

I've had the same problem for years. I've disabled all plugins and wiped all traces of Firefox completely several times. It just keeps hanging on several websites. When I load a heavy website such as Outlook in a new tab, it just locks up for several minutes. Every few seconds the loading wheel animates for a few milliseconds. The Mac's dock animations stop working as well.

Safari works perfectly. This just looks like sloppy coding and a substandard Mac port. Even Javascript loops cause the entire browser to hang instead of just the one tab, which is ridiculous and shows that it has poor or non-existent multi-threading. The Windows version works perfectly with all the same stuff installed.

Hi, Locutus,

If you have a similar problem with Firefox and the suggestions here didn't help, you should ask a new question in the support forum. See Mozilla Support rules and guidelines: ... For support requests, do not re-use existing threads started by others, even if they are seemingly on the same subject..

A new question will list details about your system and other troubleshooting information. You can use this link or the "Ask a Question" link on the Get community support article to start the process.