All your bookmarks, and all personal information such as passwords etc., should be retained after upgrading. That being said, backing up is never a bad idea. Using the Bookmarks menu, select Organize Bookmarks. At the top of that page there is an Import and Backup option. Select the backup option and choose where to save the file.

Thanks very much for your help. I have saved the file now and so will upgrade. Sean

<<< Using the Bookmarks menu, select Organize Bookmarks. At the top of that page there is an Import and Backup option. >>>

Islander Circe:

I don't see Import and Backup after selecting Organize Bookmarks. (It just opens the Library page.) Was that option not in v. 3.6.6 (my current version)?

Thanks.

All worked sweet for me as "IslanderCirce" suggested, no problems. I didn't need the file I saved, all transferred over in the upgrade. Maybe it is your current version.

SteveRay, I've included a picture showing where it should be...if you're using the Windows version. The image is from version 4 but it was the same in ver 3.

The Mac is different & there are instructions here: https://support.mozilla.com/en-US/questions/830398 Go to the answers further down the page.