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Repeated Hangs and Eats up CPU on Mac

  • 7 replies
  • 1 has this problem
  • Last reply by John99

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It's getting worse and worse. I have to force quit every time. I've tried turning off add ons and it helps but its not a practical solution as I work in Web Design and use most of these plug ins to be sure the sites I design will WORK in Firefox. So at least some of them have to remain on.

The odd thing is I have the exact same plug ins on the PC at work and DO NOT have the problem. Therefore whatever it is seems to be between Firefox and Mac.

Can anyone please suggest a fix?

All Replies (7)

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To solve your problem you can try out these steps.

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Hello starhorsepax, if the problem is an add-on then the solution is to disable it !

check IF after you delete in your profile folder the User.js file, the problem exist.

(The user.js file does not exist by default. If you create the file forget it, if not, note that some programs create and write in the User.js file also).

thank you

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I believe I did mention that disabling is not an option. I work in web design: these add ons are ones required. In fact I'm working on a Firefox problem child today: the site works in every browser (Chrome, Safari etc) except Firefox. Without the add ons I can't find the problem to fix it.

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Regardless of the fact that you need the addons to work if you wish to sort out a Firefox problem it is going to help if you are able to show that Firefox works OK other than with specific addons installed.

If the problem is there without addons it is a Firefox problem, otherwise it may be a problem with an addon.

If it is a Firefox problem, is it with a specific version ?

Although not relating specifically to hangs and CPU use there is a Memory issue with Firefox on a Mac that has been fixed recently in Fx28

Have you tried upgrading to Firefox 28 does that help ?

Another potential workaround is to use multiple profiles and only use the minimal number of installed addons required for the task in hand.

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I did try updating and starting in safe mode. In the beginning it worked, but as I went on it did start to suck more and more power. More than the other browsers anyway. can anyone point me at a link on how to do multiple profiles?

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We do no actually document using multiple profiles or multiple versions as it is considered unnecessary for ordinary users. It is however very handy with troubleshooting or I imagine in web development where you may wish to check behaviour in different versions or different configurations of a browser. You just need to be slightly careful that you do not lose track of and accidentally delete profiles or content of profile directories. Backing up profiles may be advisable.

I will add more information in a follow up post.

Also note use the -no-remote argument if you are using simultaneous instances of Firefox, but do not use that on the default profile.

If you have problems or need more suggestions please post back. There are other advanced features that may help.

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Using multiple profiles is not something we shout about on this forum. It is I think considered too advanced. It does have some dangers in that you may accidentally delete profiles for instance. It is however possible to manually backup profiles, and that may be a good precaution to take. I would also strongly suggest that you follow this good practice (At least until you are proficient enough to manually recreate and modify profiles)

  1. Normally use the locations suggested by Firefox
    It is easier and safer
    • Always use an empty folder
      Other contents disappear when the profile is removed
    • Never nest profiles within each other
      As above,delete mother, lose child also
  2. Do not rename profiles
    Confusing, profile names and folder names mismatch
  3. Do not delete profiles
    Just remove shortcuts if not in use. Delete the wrong one and you lose settings, passwords & bookmarks etc

Uses of multiple profiles include

  • Testing, with clean or temporary profiles
  • Different users, or different work type within the same OS account. That may include different bookmarks files &/or a different set of addons.
  • Running multiple Firefox versions &/or multiple instances of Firefox simultaneously.

There are other methods of creating profiles but the best is probably to use Firefox's built-in profile manager.

Read up some of the articles, and if you want to try anything and are unsure post back.