You can restore bookmarks from the "bookmarkbackups" folder in your profile folder.

The name of automatically created JSON bookmarks backups in the bookmarkbackups folder includes a total item count (folders and separators included) and an hash value to prevent saving the same backup more than once. You can this count to select which backup to restore. You also see this count in the Library Restore menu drop-down list.

• bookmarks-YYYY-MM-DD_<item count>_<hash>.jsonlz4.