Firefox Support Forum

FF uses 100+ CPU on my otherwise totally fast up-to-date MacBook. This, despite doing all the fixes suggested, repeatedly.

It has gotten so bad that it constantly overheats my Mac, causes my fan to go on full blast non-stop, even when it's in the background, so I basically have to stop using it.

Mozilla needs to get serious and overhaul this heavy-use browser.

Why doesn't Firefox 26.0 doesn't show my downloads anymore!!!!

In the last version of firefox 25.0.1 still showed the download window when using downloadhelper, now in version 26.0 I no longer see the download box. When I go to about:config my setting are as they were in version 25.0.1 but there is still no download box opening. Will this issue be fixed and or will I need will downgrade to version 25.0.1.????

MacBook Pro early 2011 15" fan starts spinning up when I use Firefox even just one tab/window open slowly as I open a couple more tabs starts spinning more and more. It is unusable. I have done all the resets recommended, extensions removed etc and the problem is the same. I am using Qantam. Thanks

The main reason I still use Chrome is to keep my laptop fan from turning on when I watch YouTube videos. This then leads me to use Chrome for other reasons as well. I would prefer to use Firefox, but I don't like it when my fan turns on. My Firefox is up to date according to me preferences page.

I have tried unchecking "Use hardware acceleration when possible" and restarting Firefox, but the fan still comes on.

What's the solution?

I am curious as to why the silverlight plugin ramps the fans up (3k+ rpm) when I am watching prime video's in Firefox, but when watching the same video's in Safari, the fans a pretty much the standard 2000 (2k - 1.5k) rpm. Happens with youtube too. Safari and web videos is way quieter and I guess I just don't understand why the difference.

Is there a way to get FF to throw a little less power at these video's so as to not light the fans off so much? It can really drown out the video audio depending on what it is. As it is, I use Safari for watching video's, but hate having to have 2 browsers open.

I have been using Firefox for more than 10 years now. it is the best browser out there. However, starting from last year I have been noticing that my computer's fan is almost always working which takes too much of my battery and I figured that Firefox is the main issue (I did so many research and tests %100 sure). Later, I herd about the new Firefox quantum, and decided to wait and not switch to another browser. the new one was released and I installed it the very first day. I was super happy that it's much faster and use less memory than other browsers (that's right). However, lately (about a month) I noticed the same the fan is always working again, so I check the task manager and found my dear Firefox quantum acting up again even though 3 taps are opened.

I really need help with this issue to stay using Firefox, I am tired of this issue and really considering switching to another browser because this is just not good at all. and I could not find any way to fix it. please see the attached pic it's just unbelievable.