I have Linux Mint installed on 3 computers at home, and all of them are almost unusably slow whenever Firefox is open. Here is the output from top:
As you can see, "Web Content" and Firefox are collectively using up nearly all of my CPU, and more than 50% (4GB+) of system memory.
I have never had this problem in the past with Debian or Ubuntu, but it is occuring on every computer I've installed Mint on so far. This extremely high (near total) CPU/memory usage is constant, and is rendering my computer unusable.
Does anyone have ideas about how to fix this? If there is no fix, how can I keep this "Web Content" application from running at all?
Best Answer
this is a common problem causing nothing but the battery wasted energy decreasing unplugged operation time significantly.
the cause of the problem appears to be very simple: you may have too many tabs opened each having bulky and useless endless loops running java-scripts.
those java-scripts are usually not origin of the web site you are working with but an ad based 3rd parties from somewhere else trying to collect some info from your FFox session or just to display switching ads on a side.
the simple (but not unique) solution would be to install NoScript plugin - causing immediate effect - Web Content process CPU consumtion will decrease almost to 0%.
so keep NoScript installed on all your FFox'es and keep track on what domain you are actually allowing scripts from to be executed very carefully.
it's a good practice to allow only original domain scripts for permanent (a choice "allow") to have the web site you are visiting to display correctly all the useful information, but to keep side or extra domains only in "forbid" or "temporary allow" mode so the next FFox load will keep all these unwelcome scripts banned again.