Hi puhalov, did you notice any other changes in Firefox around the same time?

Also, could you check your desktop for a folder named Old Firefox Data? If you find that folder, could you check inside for a semi-randomly-named folder and inside that folder, for a folder named bookmarkbackups? These files should be dated. Are there any that are recent enough to possibly have your missing bookmarks?

I did not notice other changes. The bookmarks were their in the early afternoon, later, around 3 PM they were gone. The old files folder is on the desktop and the bookmarks files for different dates, however, I don't have the s/w to open any of the files. I am a novice user, all help will be appreciated. As I said, the restore process instructions show a drop down list of available dates does not go back to before the bookmarks disappearance. Is this a browser problem? I don't know how to contact Mozilla regarding a possible browser problem. Thanks again.

puhalov said

As I said, the restore process instructions show a drop down list of available dates does not go back to before the bookmarks disappearance.

At the bottom of the Restore menu, below the specific dates you will find "Choose File". Click that to open a file browser dialog. Then use that to open your latest old bookmark backup file from the Old Firefox Data folder on your desktop. If that works, Firefox will roll back your bookmarks to that date.

More info: Restore bookmarks from backup or move them to another computer.

jscher200, I can't thank you enough. If we could get together I would hug you and buy you a drink of your choice. I can't describe to you how many bookmarks I have, all equally important to me. I rely on my PC to keep me occupied during the day as I rest from my chores. Thank you very much, Tony (Ante) Puhalovich An Octogenarian