Hi Didier If you notice you lost bookmarks or accidentally deleted bookmark(s) and you haven't closed Firefox yet then you can use "Organize -> Undo" in the bookmarks manager (Bookmarks -> Show All Bookmarks) to undo this action and restore bookmark(s) you deleted accidentally or otherwise lost/misplaced. You may have to use Undo more than once (Firefox keeps a full undo history stack for the current session). Otherwise you can consider to restore the bookmarks from a JSON backup in the bookmarkbackups folder. *Bookmarks -> Show All Bookmarks -> Import & Backup -> Restore This will replace all current bookmarks and you lose bookmarks that were added since that backup was created, so you may want to create an HTML backup on beforehand.