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Firefox is overheating my mac

  • 5 replies
  • 1 has this problem
  • 8 views
  • Last reply by FredMcD

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I am running Firefox 38.0.1 on my Mac, which is using Yosemite 10.10.3. I am also using SMC Fan Control.

When I run Firefox, the temperature on my Mac shoots up from about 43C to around 78C and hovers there, causing my fans to revs way up. I am not running video or ANY other programs in the background. I have exactly 2 websites open now, Yahoo.com and this Firefox help page. The only other program running is Astrill VPN.

When I close Firefox and use Safari to run the exact same websites, plus about 9 others, the problem disappears and my macbook pro runs at a steady mid to lower 40s Celsius.

This began when I updated to the newest version of Firefox. No other software was installed prior to that for over a month and since the problem began, only an update to my adobe flash player has been installed.

I don't like Safari. I much prefer to use Firefox, but not with the system rapidly heating up as it is.

You guys really need to look into this.

I am running Firefox 38.0.1 on my Mac, which is using Yosemite 10.10.3. I am also using SMC Fan Control. When I run Firefox, the temperature on my Mac shoots up from about 43C to around 78C and hovers there, causing my fans to revs way up. I am not running video or ANY other programs in the background. I have exactly 2 websites open now, Yahoo.com and this Firefox help page. The only other program running is Astrill VPN. When I close Firefox and use Safari to run the exact same websites, plus about 9 others, the problem disappears and my macbook pro runs at a steady mid to lower 40s Celsius. This began when I updated to the newest version of Firefox. No other software was installed prior to that for over a month and since the problem began, only an update to my adobe flash player has been installed. I don't like Safari. I much prefer to use Firefox, but not with the system rapidly heating up as it is. You guys really need to look into this.

All Replies (5)

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Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options)
key, and then starting Firefox. Is the problem still there?


Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

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Yes it is.

Shot from 44C to 72C in less than 45 seconds.

And once I quit Firefox, the temp just plummets.

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Does this also happen with all plugins disabled ("Ask to Activate")?

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Unfortunately, yes.

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Start your Computer in safe mode with networking. Then start Firefox. Try Safe web sites. Is the problem still there?

Starting The Computer In Safe Mode;
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