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Closing a few tabs does not slim down memory usage

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

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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)

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

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Tnx, will try that.

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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.

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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.