Try this: * download the Firefox installer and save the file to the desktop<br>*https://www.mozilla.org/en-US/firefox/all/ * start the installation with a double-click on the desktop icon 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 <b>about:config</b> page. *browser.tabs.remote.autostart = false *browser.tabs.remote.autostart.2 = false *http://www.ghacks.net/2016/07/22/multi-process-firefox/ You can open the <b>about:config</b> 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 You can try to disable hardware acceleration in Firefox. *Options/Preferences -> Advanced -> General -> Browsing: "Use hardware acceleration when available" You need to close and restart Firefox after toggling this setting. *https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems You can check if there is an update for your graphics display driver and check for hardware acceleration related issues. *https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration