Hi Jean375, It seems that Classic Theme Restorer would be the solution. You can find it [https://addons.mozilla.org/en/firefox/addon/classicthemerestorer/ here]. Romain

Do you mean that you used the refresh feature in Firefox and lost your extensions and themes? When you Refresh/Reset Firefox then a new profile is created and some personal data (bookmarks, history, cookies, passwords, form data) is automatically imported. The current profile folder will be moved to an "Old Firefox Data" folder on the desktop. Installed extensions and other customizations (toolbars, prefs) that you have made are lost and need to be redone. It is possible to recover data from the "Old Firefox Data" folder on the desktop, but be cautious not to copy corrupted files to avoid carrying over problems. You can copy files like these from the "Old Firefox Data" folder on the desktop 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