Hi, you should be using Firefox version 52.9.0esr as is last secure browser for XP/Vista as of a few days ago. There is no further supported browsers planned. You should update to a supported Operating System as soon as you can. Linux is a option. Pick your Language for 52.9.0esr : https://ftp.mozilla.org/pub/firefox/releases/52.9.0esr/win32/ Before you do : *https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles *https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer Tabs, is this what you wanted to know ? *https://support.mozilla.org/en-US/kb/tabs-organize-websites-single-window