You can just copy the full profile of Firefox and move it to a new computer.

See https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data#w_finding-your-profile-without-opening-firefox

Thank you for your response.

I moved the entire file that was in the old computer at Users/1/AppData/Roaming/Mozilla/Firefox/Profiles to the same directory on the new computer. When I restart Firefox, the error says that it cannot load the profile. Do I need to reboot the computer first? Or is there another solution? Thank you!

What's the version number of old Firefox? It might be a compatibility issue.

I cannot run it, so I do know the version number. It was running on Win 7 Pro and was updated to whatever the most recent version is available.

Hello, I can see on my Mozilla Account page that I was running Firefox 115 on Windows 7 Pro. Is there a compatibility issue importing into Firefox 144 on Win 10?

OK, there is good progress. It now appears that history, saved passwords, and extensions have been successfully moved to the new Mozilla installation. But not the tabs. Is it possible to find the tabs in the old Profile and manually move them to the new Profile?

Check out this article: How to restore a browsing session from backup

Sorry for the delay in returning.

I followed the instructions in "How to restore a browsing session from backup" but I must be doing something incorrectly.

When I move the sessionstore.jsonlz4 file from my old computer into the AppData\Roaming\Mozilla\Firefox\Profiles folder and restart Firefox, it returns to the last open session and not the session from the old computer.

I notice that there are also Profiles in the AppData\Local folder. Should the old sessionstore.jsonlz4 also be moved there?

Please advise.

On your old drive, one folder up from Profiles, you will find a pair of .ini files: installs.ini and profiles.ini. These index files tell Firefox what your profile folder names are, so if you setting aside the new profile folder and trying to use the old ones, copying over those two .ini files to replace the current ones should help.

You can ignore Local, that hold the cache and other temporary/transient data.