This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Closing a few tabs does not slim down memory usage

  • 4 replies
  • 6 have this problem
  • 3 views
  • Last reply by cor-el

more options

Firefox 55.0, latest Win 10: Firefox operates properly. HOWEVER, by chance, using Task Manager, I noticed that when I close a few tabs, the amount of memory space Firefox uses does not decrease. If I close Firefox down and then re-launch, Task Manager does show that Firefox is using less memory. This strikes me as a big. Is there any way to fix this, or any add-on?

Firefox 55.0, latest Win 10: Firefox operates properly. HOWEVER, by chance, using Task Manager, I noticed that when I close a few tabs, the amount of memory space Firefox uses does not decrease. If I close Firefox down and then re-launch, Task Manager does show that Firefox is using less memory. This strikes me as a big. Is there any way to fix this, or any add-on?

All Replies (4)

more options

There are buttons on the about:memory page to reduce memory that can try.

more options

Tnx, will try that.

more options

I have the same problem with 56.0.1. I go from about 390 MB to 3.7 GB in task manger with only 5 or 6 tabs open and a couple that are mostly static. It gets so bad that Firefox starts short burst of not responding and not responding to keyboard and mouse input immediately.

more options

You can try to modify multi-process settings to see if this has effect.

  • set dom.ipc.processCount to 1 if it is currently set to a higher value (4)
  • disable multi-process windows in Firefox

You can disable multi-process windows in Firefox by setting these prefs to false on the about:config page.

  • browser.tabs.remote.autostart = false
  • browser.tabs.remote.autostart.2 = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.