In the event that the passwords information is lost, you should record all information in a separate text file somewhere else on your hard drive, or written down. You can easily copy and paste if you need to do so. If you are concerned about someone else looking at that file, you can compress it using a password.

Password Exporter {web link} This extension allows you to export your saved passwords and disabled login hosts using XML or CSV files that can be imported later.

extensions(add-ons): it would be better to download them fresh.

Copy Extensions to Clipboard {web link} Kopiert eine Auflistung aller installierten Add-ons, Plugins und Themes in die Zwischenablage Copies a list of all installed add-ons, plugins and themes to clipboard

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 for stored intermediate certificates (Certificate Manager)
• persdict.dat for words you added to the spelling checker dictionary
• permissions.sqlite and possibly content-prefs.sqlite for Permissions and Site Preferences
• sessionstore.js for open tabs and pinned tabs and tab groups

• https://support.mozilla.org/kb/Recovering+important+data+from+an+old+profile
• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

You can use this button to go to the current Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
• http://kb.mozillazine.org/Profile_folder_-_Firefox

Thank you, FredMcD and cor-el for your support! Now my problems are solved.

Regards, Roger