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

Why is Firefox Using Too Much Memory?

  • 3 replies
  • 8 have this problem
  • 22 views
  • Last reply by Dr Genius

more options

Been having this problem for a while with firefox, seems like an update last summer and the past upgrade things have changed. Task Manager shows multiple tabs open in firefox, I had two tabs open, one for my homepage and another for a website I was visiting, firefox shows a lot of activity on one tab and thing there's 3 other tabs open.

This causes my computer to lag and be unresponsive, everything application, every function, the task bar, everything lags and slow to respond and responds in a choppy way. This has been going on for sometime and is a real headache, I do my work and use firefox considerably, I open multiple tabs and work on certain websites, Firefox uses 500-1,000+ MB and 80-90% memory, why is that?

Been having this problem for a while with firefox, seems like an update last summer and the past upgrade things have changed. Task Manager shows multiple tabs open in firefox, I had two tabs open, one for my homepage and another for a website I was visiting, firefox shows a lot of activity on one tab and thing there's 3 other tabs open. This causes my computer to lag and be unresponsive, everything application, every function, the task bar, everything lags and slow to respond and responds in a choppy way. This has been going on for sometime and is a real headache, I do my work and use firefox considerably, I open multiple tabs and work on certain websites, Firefox uses 500-1,000+ MB and 80-90% memory, why is that?
Attached screenshots

Chosen solution

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

  • set number of content processes to 1 if it is currently set to a higher value (4)
    Options/Preferences -> General -> Performance
    remove checkmark: [ ] "Use recommended performance settings"
  • disable multi-process windows in Firefox

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

  • browser.tabs.remote.autostart = false

Note that the previously used opt-in pref browser.tabs.remote.autostart.2 is no longer supported in Firefox 58+. You can reset browser.tabs.remote.autostart.2 via the right-click context menu to the default value to have this this pref removed on the next start.

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.

Read this answer in context 👍 2

All Replies (3)

more options

Chosen Solution

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

  • set number of content processes to 1 if it is currently set to a higher value (4)
    Options/Preferences -> General -> Performance
    remove checkmark: [ ] "Use recommended performance settings"
  • disable multi-process windows in Firefox

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

  • browser.tabs.remote.autostart = false

Note that the previously used opt-in pref browser.tabs.remote.autostart.2 is no longer supported in Firefox 58+. You can reset browser.tabs.remote.autostart.2 via the right-click context menu to the default value to have this this pref removed on the next start.

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.

more options

Thanks Cor-el, looks like that worked, not much of a headache anymore.

more options

Why on earth is the default setting so clunky then? seems absurd that we all have to tweak settings for Firefox to function in an acceptable fashion. :-(