You can try this : https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

I now see that your having some video driver issues : Please re-install or update your video drivers. https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration Try using No Hardware Acceleration

Please note Microsoft can replace your drivers with there own. https://www.howtogeek.com/263851/how-to-prevent-windows-from-automatically-updating-specific-drivers/

Please Note thare has been issues with Kaspersky software, please update or check for new version.

This may help since you have only 8gigs of Ram: NOTE : You enter the recommend size that shows into both boxes MICROSOFT VIRTUAL MEMORY

You may want to try this: Open the System Folder then Click on left side Advanced System Settings which opens System Properties click the Advanced Tab then click Performance button Settings then the Advanced Tab then Click the Change under Virtual Memory click Custom Size and Change Size to where it says Recommended Size then Click Set and then Click Apply then please Re-boot.

System - -> Advanced System Settings --> System Properties - -> Advanced Tab - -> Change Virtual Memory - -> Custom Size - -> ENTER Recommended Size - -> Set - -> Apply-- > Reboot

Please let us know if this solved your issue or if need further assistance.

HI, Pkshadow and thank you for trying to help me.

I updated the video drivers to the latest version 384.76.

Tried with Hardware acceleration turned off. Kaspersky turned off. Firefox in Safe mode. But I can not see how this is connected with the leaking memory usage when uploading big files.

I have 16GB of RAM not 8.

Memory report part with usage: https://pastebin.com/8sixha8R

Explicit Allocations

2,216.78 MB (100.0%) -- explicit ├──1,933.91 MB (87.24%) ── heap-unclassified ├─────89.58 MB (04.04%) -- js-non-window │ ├──55.60 MB (02.51%) -- zones │ │ ├──42.36 MB (01.91%) ++ zone(0xf31800) │ │ └──13.24 MB (00.60%) ++ (13 tiny) │ ├──31.88 MB (01.44%) ++ runtime │ └───2.09 MB (00.09%) ++ gc-heap ├─────80.35 MB (03.62%) ++ (23 tiny) ├─────67.01 MB (03.02%) -- gfx │ ├──65.78 MB (02.97%) ── heap-textures │ └───1.23 MB (00.06%) ++ (6 tiny) └─────45.93 MB (02.07%) ++ window-objects

When I start uploading the file. Firefox reads the file and stores it in Memory, why is that? So when I upload 2x2GB files, Firefox usage is above 4GB and because it is a 32 bit version, it just crashes!

Tried uploading the files to the same website cloud.mail.ru with the browser Chrome and there was no memory leakage, so it is something connected with FF memory management :).

See below screenshots - First one is when opening the website and the second one is when the file is beeing uploaded and already Firefox has put it in memory.

When multi-process windows in Firefox is enabled then Firefox will use more memory and may be less responsive. Try to disable multi-process windows in Firefox to see if that has effect.

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'll be careful" to continue.

• http://kb.mozillazine.org/about:config

• http://www.ghacks.net/2016/07/22/multi-process-firefox/

I have already tried this. The first thing that I do was to turn muli-processing off, but no result.

With a newly installed Firefox is the same. Please test on your systems to confirm.