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Why does my Firefox keep turning into a runaway application?

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  • Last reply by cor-el

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I have a 2009 MacBook Pro with a recent problem. When I am running some applications, Firefox becomes a runaway application. It uses close or up to 100% of the CPU, and the laptop runs fast and hot. I can stop this process by closing Firefox, but of course that doesn't solve the problem. I am using Snow Leopard and the latest version of Firefox.

I have a 2009 MacBook Pro with a recent problem. When I am running some applications, Firefox becomes a runaway application. It uses close or up to 100% of the CPU, and the laptop runs fast and hot. I can stop this process by closing Firefox, but of course that doesn't solve the problem. I am using Snow Leopard and the latest version of Firefox.

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Hello,

Try disabling graphics hardware acceleration. Since this feature was added to Firefox, it has gradually improved, but there still are a few glitches.

You might need to restart Firefox in order for this to take effect, so save all work first (e.g., mail you are composing, online documents you're editing, etc.).

Then perform these steps:

  • Click the orange Firefox button at the top left, then select the "Options" button, or, if there is no Firefox button at the top, go to Tools > Options.
  • In the Firefox options window click the Advanced tab, then select "General".
  • In the settings list, you should find the Use hardware acceleration when available checkbox. Uncheck this checkbox.
  • Now, restart Firefox and see if the problems persist.

Additionally, please check for updates for your graphics driver by following the steps mentioned in the following Knowledge base articles:

Did this fix your problems? Please report back to us!

Thank you.

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What kind of application(s) are causing this problem?

Is this with visiting specific web pages?

Is there JavaScript involved or plugins?