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I have a Mac running Snow Leopard 10.6.7, I am using Firefox 4.0.1 and I have installed for it the Firebug 1.7.3 extension.

Some time, while I am using the browser to work for my website, Firefox starts to hard load something that I don't know: if I go to the Activity Monitor panel I see that it is using almost all the CPU!

So I have to force quit the application:

  • if I start a new session I have no problem;
  • if I restore the previous session sometime it is all right but some other no (Firefox still use a lot of CPU) and so I must start a new session loosing all my opened tabs.

What is the problem? There is a way to solve this issue? If so, how can I do?

P.S.: I noted that sometime all this happen after I use the Mac Sleep function (caching problem?) but sometime it is completely random.

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migrated from ux.stackexchange.com Jun 30 '11 at 2:55

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Kind of an annoying comment to make, but still... Maybe this is a bug that was solved with Firefox 5. I suggest you upgrade, retest and update your question. –  Doc Jul 1 '11 at 0:16
@The White Phoenix - This problem happens to me from version 3 if not from earlier versions! –  user502052 Jul 1 '11 at 1:07
Happens for me still, in all versions of firefox/firebug, on all computers, all operating systems. This is a horrendous bug in firebug, and will apparently never be fixed... I'm about ready to move to Chrome for development. –  BlueRaja Mar 7 '13 at 10:40

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