You can export the bookmarks on the old computer and import the bookmarks on your current computer. *Bookmarks > Show All Bookmarks > Import & Backup *https://support.mozilla.org/kb/restore-bookmarks-from-backup-or-move-them *http://kb.mozillazine.org/Backing_up_and_restoring_bookmarks_-_Firefox ----- You can copy files like these to the current Firefox profile folder to recover specific data. *bookmarks and history: places.sqlite *bookmark backups: JSON backups in the bookmarkbackups folder *SQLite files like cookies.sqlite (cookies) and formhistory.sqlite (saved form data) *logins.json and key3.db (decryption key) for Passwords saved in the Password Manager *cert8.db and possibly cert_override.txt for (intermediate) certificates stored in the Certificate Manager *persdict.dat for words you added to the spelling checker dictionary *permissions.sqlite for Permissions and possibly content-prefs.sqlite for other Site Preferences *sessionstore.js for open tabs and pinned tabs and tab groups You can use this button to go to the current Firefox profile folder: *Help > Troubleshooting Information > Profile Directory:<br>Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder *http://kb.mozillazine.org/Profile_folder_-_Firefox