'''[https://addons.mozilla.org/en-US/firefox/addon/places-maintenance/ Places Maintenance]''' {web link} Allows to run Maintenance tasks on the database that drives Places, the bookmarks and history module behind Firefox. ------------------------ '''https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save''' Note: Some software, like Advanced SystemCare with Surfing Protection, can protect files in the Firefox profile folder against changes. If you have such software then check the settings or uninstall this software. -------------------------- Some problems occurs when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again; * Make sure your Internet security software is up-to-date (i.e. you are running the latest version). * Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see '''[https://support.mozilla.org/en-US/kb/configure-firewalls-so-firefox-can-access-internet Configure firewalls so that Firefox can access the Internet.]''' {web link}