Ok so it looks like I broke my firefox online profile now somehow. Ram usage drop was really slow like 10-30 seconds. After closing all tabs except for 1 ram usage start to SLOWLY decrease but it stops at 3,7GB.
![firefox uses a lot of memory firefox uses a lot of memory](https://i.ytimg.com/vi/5z5X_QAjMpM/maxresdefault.jpg)
Opened few tabs, ram usage goes to 4.2GB.
#Firefox uses a lot of memory Pc#
3,4GB of PC RAM usage on firefox safe mode start. It says that 2 opened tabs and addons use 100MB of memory which is not true because browser at this moment uses 1060MB. I also tried checking about:performance menu but there is nothing interesting here. It does not matter how I close tabs - using right click context menu (close other tabs, close tabs to the right), using X on tabs, or using add-on to close all tabs except for pinned ones. After I close them it slowly drops to 3.5GB instead of returning to 3.2GB. For example if I open 10 more tabs except for 2 that always open so I have 12 tabs I have 3.6GB memory usage. Restarting browser helps - ram uasge rises from 2.4GB to 3.2GB only (800MB for 2 tabs) but every new opened and closed tab seems to stay in memory. I had trouble writing this post with 2 tabs open because of 3.3GB ram usage! I also have terrible lags because of this - browser hangs up every few seconds for few seconds. I have 8GB of ram so 3GB of usage from 1 open tab is crazy. So it looks like firefox has multiple tabs stored in ram and opening new tabs just rewrites that memory instead of allocating new one. However when I open 10-20 tabs again RAM usage does not rise (maybe slightly, like 5.3GB). It goes from 2.4GB (system only usage) to 5.0GB and does not drop after closing tabs. In firefox 78.0.1 after doing this (opening and then closing multiple tabs "to the right" using new context menu added in 78) my ram usage does not drop. My standard browsing habit consists of launching browser with 1 pinned tab and 1 home page (so 2 tabs only), then opening 5-10 tabs from my bookmarks, checking pages then closing them and leaving only 1 pinned page open.
![firefox uses a lot of memory firefox uses a lot of memory](https://www.lifewire.com/thmb/Lu5C1NMB5UJQTXFj7UySqa6d7A4=/1499x1001/filters:no_upscale():max_bytes(150000):strip_icc()/014-prevent-firefox-from-using-too-much-memory-4772084-8de6b4849e5842848ee7479001b044da.jpg)
After updating from 77 (I think it was 77.0.2?) to 78.0.1 I started noticing terrible firefox performance after a few minutes of browsing.