See this -> [https://support.mozilla.org/en-US/kb/disable-or-remove-add-ons?esab=a&s=disable+extensions&r=0&as=s Disable or remove Add-ons]

You can try these steps in case of issues with web pages: You can reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files. *Hold down the Shift key and left-click the Reload button *Press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux) *Press "Command + Shift + R" (Mac) Clear the cache and cookies only from websites that cause problems. "Clear the Cache": *Firefox/Tools > Options > Advanced > Network > Cached Web Content: "Clear Now" "Remove Cookies" from sites causing problems: *Firefox/Tools > Options > Privacy > "Use custom settings for history" > Cookies: "Show Cookies" Start Firefox in <u>[[Safe Mode|Safe Mode]]</u> to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem. *Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance *Do NOT click the Reset button on the Safe Mode start window *https://support.mozilla.org/kb/Safe+Mode *https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes