@jess1379 My comment to dianet was directed at a situation where a hard drive had just been replaced and Opera was installed fresh on it. In that case, unless one can copy-in various previously-saved profile files from 'somewhere' that contain settings, preferences, bookmarks, etc., nothing else exists to recover those files on a brand new drive.
In some cases, users may have created full hard-drive image files on external media prior to replacing their drive, from which files can be recovered; in other cases, they may have previously backed up their data/personal/settings files to a simple flash drive; in still other cases, they may have used a 'sync' feature built in to their browser to recover browser file copies previously placed up on the browser-maker's servers by the browser - in which case, they can carefully bring them back down to a new installation and thus recover them. My point was simply that if a user hasn't backed up or sync'd his user files in some way ahead of a disaster, there exists no other way to recover their contents afterward.
I always recommend users at least make backup copies of all their critical data/personal/settings files on some form of external media for any installed software on their system and to keep that backup updated as often as necessary. Using a program's built-in "sync" function for backing up files too easily risks losing the sync-saved files located up on the sync server by making simple mistakes that, instead of recovering the sync'd files, instead overwrites those sync-saved files on the server with the current new-installed files from the user's system which don't contain their desired data. Though sync is convenient and some users employ it as a kind of backup, it is NOT intended for true backups - too many things can go wrong on the user's system or the sync server.
Put another way, there is absolutely no subsitute for making backups of the files that matter to a user and keeping those backups somewhere off the system - IMHO, physically apart from the system and offline, though some people do maintain formal cloud backups instead. YMMV.