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Why does Firefox use so much memory ?

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I have 721 tabs open and Firefox uses about 2 GB of memory. Why doesn't Firefox simply memorize only the URLs rather than the whole pages ? Firefox becomes sluggish. The whole PC seems to be impacted ...

I have 721 tabs open and Firefox uses about 2 GB of memory. Why doesn't Firefox simply memorize only the URLs rather than the whole pages ? Firefox becomes sluggish. The whole PC seems to be impacted ...

All Replies (4)

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Hi Toon_, Firefox only uses about 200 MB of memory.

Everything else - extensions, themes, plug-ins, Content Blocking, hardware acceleration, tabs, etc. - are all on the User.

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Hi Slippin' Cheese, How can I find out then which of these components use what amounts of memory ?

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Firefox has a built-in Task Manager which will tell how much memory is being used by extensions and tabs.

Click Menu -> More -> Task Manager

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Also, see this article:

Task Manager - see what tabs or extensions are slowing down Firefox https://support.mozilla.org/en-US/kb/task-manager-tabs-or-extensions-are-slowing-firefox