My bad, sorry... What about this, from [1,2]? > To disable e10s/multiprocess go to about:config by typing it in your URL bar. Search for browser.tabs.remote.au

My bad, sorry... What about this, from [1,2]? > To disable e10s/multiprocess go to about:config by typing it in your URL bar. Search for browser.tabs.remote.autostart using the search box on about:config. There may be multiple results. Set them all to false and restart the browser (if there are no entries, create it as a boolean and set it to false). [1] https://support.mozilla.org/es/questions/1191898 https://support.mozilla.org/es/questions/1191898 [2] https://support.mozilla.org/es/questions/1191898 https://support.mozilla.org/es/questions/1191898