Your personal data is stored elsewhere in the Firefox profile folder, so you won't lose your bookmarks and other personal data when you uninstall and (re)install or update Firefox.

• http://kb.mozillazine.org/Profile_folder_-_Firefox

Make sure that you meet the System Requirements (GTK+ and GLib) for the current Firefox version.

• https://www.mozilla.org/en-US/firefox/35.0/system-requirements/

You can find the full version of the current Firefox 35.0 release in all languages and for all Operating Systems here:

• https://www.mozilla.org/en-US/firefox/all/

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backup of files that you choose.

OPIE {web link} Import/Export extension preferences