Uninstall and Reinstall your Addons *[[Disable or remove Add-ons]] *[[Remove a toolbar that has taken over your Firefox search or home page]] Troubleshot your Addons https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

Do you see the Multifox item to open a new window in the File of Firefox menu? ----- You will see a "New Identity Profile" (Ctrl+Alt+M) in the "Firefox > New Tab" menu and in the File menu (press F 10 if the menu bar is hidden) and in the context menu if you right-click a link.<br /> Choosing that menu entry will open a new window with a new set of cookies marked multifox-profile-2 in the cookie manager. ---- It is possible that there is a problem with the file(s) that store the extensions registry. Delete the files extensions.* (e.g. extensions.sqlite, extensions.ini, extensions.cache) and compatibility.ini in the Firefox profile folder to reset the extensions registry. *https://support.mozilla.org/kb/Profiles New files will be created when required. See "Corrupt extension files": *http://kb.mozillazine.org/Unable_to_install_themes_or_extensions *https://support.mozilla.org/kb/Unable+to+install+add-ons If you see disabled, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left side of the Search Bar (or click the "Find Updates" button in older Firefox versions) to check if there is a compatibility update available. If this hasn't helped then also try to delete the addons.sqlite file.