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Firefox slows down to a screeching halt.

  • 12 cavab
  • 26 have this problem
  • 1 view
  • Last reply by SlowAFfox

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It seems firefox can't handle having 18-20 tabs open for 30 minutes since restart. Memory chewage reaches 2GB and upwards rapidly and consistently, however that's not even the main problem as I have plenty of RAM left still. The real problem is that as soon as Firefox has eaten more than 1.5GB it starts to slow down dramatically until refusing to respond completely. The issue does persist even after "restarting without plugins" and in "safe mode". That has been happening for the last half a year or so, and I don't remember firefox being so fragile before.

In addition, flash-heavy sites like Facebook, Twitch, Twitter and Coub, even when opened alone are a nightmare to browse through, and having any 2 of them opened at the same time frequently stalls the browser entirely.

Right now I have 25 tabs open in safe mode(Including the support tabs I opened to try to fix this), Firefox is at 2100MB of RAM and 40% of CPU and barely allows me to write as the input is lagging. Please tell me there is a fix to this.

Edit: Tried attaching a small screenshot of the resource manager but it seems firefox couldn't handle it. Retrying.

It seems firefox can't handle having 18-20 tabs open for 30 minutes since restart. Memory chewage reaches 2GB and upwards rapidly and consistently, however that's not even the main problem as I have plenty of RAM left still. The real problem is that as soon as Firefox has eaten more than 1.5GB it starts to slow down dramatically until refusing to respond completely. The issue does persist even after "restarting without plugins" and in "safe mode". That has been happening for the last half a year or so, and I don't remember firefox being so fragile before. In addition, flash-heavy sites like Facebook, Twitch, Twitter and Coub, even when opened alone are a nightmare to browse through, and having any 2 of them opened at the same time frequently stalls the browser entirely. Right now I have 25 tabs open in safe mode(Including the support tabs I opened to try to fix this), Firefox is at 2100MB of RAM and 40% of CPU and barely allows me to write as the input is lagging. Please tell me there is a fix to this. Edit: Tried attaching a small screenshot of the resource manager but it seems firefox couldn't handle it. Retrying.
Attached screenshots

Modified by SlowAFfox

Chosen solution

Performing a clean re-installation, this time the correct 64bit version, seems to have fixed the issue. Though I still don't know what actually caused the issue to occur in the first place, but I'm happy it's over. On a side note, it'd be nice to see the installer changed so that important choices like the installation folder and additional features weren't hidden away in an easy to overlook menu. Firefox DOESN'T detect which version must be installed, and just slaps 32bit by default. Anyway, thanks to everyone who participated in this :D

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All Replies (12)

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Did you try a new Firefox session? I.e. dot not allow Firefox to restore previous tabs and windows at startup (either automatically or by choosing "Restore Previous Session") once, so allow it to start to "Show your home page" in Options.

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Yes. This particular session was a clean restart in safe mode without plugins.

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Your info shows 2 instances of Flash Player. I would suggest uninstalling both of them, see how Firefox performs, and then reinstall Flash (if you need it.)

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Uninstalled both and tried it, but firefox just crashed when it used over 2gb+. Have to test again, still not sure if anything improved.

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HI   !

Are you using Multiprocess (e10s)  ? You can check whether you have this feature turned on as follows : • '3-bar' menu button => ' ? ' button => Troubleshooting Information • type 'about:support ' (without the commas) in the address bar and press Enter. In the first table on the page, check the row for 'Multiprocess Windows' and see whether the number on the left side of the fraction is greater than zero. If so, you are using e10s - otherwise it should read : 0/1 (Disabled).

If you are using e10s: You could turn it off as follows : Type in the address bar about:config   (press Enter) (promise to be careful, if asked) Type and search for the preferences :

browser.tabs.remote.autostart and set it's value to false   (default) browser.tabs.remote.autostart.2 and set it's value to false

Note:   the exact name of the preference may vary, but it will start with browser.tabs.remote.autostart

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Hi, have you tried using this add-on ? It should allow you to have more RAM available by releasing the RAM used by background tabs, so you shouldn't experience freezes that frequently.

Modified by mattcamp

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Uninstalling flash helped a bit, as it takes now longer to get ff frozen or severely lagging with 20 tabs. Thanks Tonnes :D I'm going to try your guys suggestions now as well, thanks.

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Disabled e10s to no effect, FF still starts to freeze on 20+ tabs and occasionally crashes. I am going to try a clean reinstall now...

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with all those tabs opening up, i wonder how many targeted ads are also trying to load up?

targeted ads, location requests, etc... are like bullets.

and unfortunately, FF is not wonder woman.

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You can consider to install the 64 bit Firefox version.

You need to uninstall the 32 bit Firefox version.

  • (32 bit Firefox) "C:\Program Files (x86)\Mozilla Firefox\"
  • (64 bit Firefox) "C:\Program Files\Mozilla Firefox\"
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I thought about that as well.

Modified by ·´¯`·...¸>-)))º> ~dbben

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Seçilmiş Həll

Performing a clean re-installation, this time the correct 64bit version, seems to have fixed the issue. Though I still don't know what actually caused the issue to occur in the first place, but I'm happy it's over. On a side note, it'd be nice to see the installer changed so that important choices like the installation folder and additional features weren't hidden away in an easy to overlook menu. Firefox DOESN'T detect which version must be installed, and just slaps 32bit by default. Anyway, thanks to everyone who participated in this :D