@haloiscool155
Hello again, no worries for the help!
About the problem, you are right — those .LOG files are just text journals of database operations, which is why they are tiny and empty. Your actual pinboard data isn't stored there.
Since you have those backup folders (Pinboard-Recovery-Backup), look inside them for these two files:
First, ldb files: Look inside the https_pinboard.opera.com_0.indexeddb.leveldb folder. The actual data is stored in the binary files named 00000X.ldb. Check if any of those are larger in size.
Second, The "Bookmarks" file: Go one folder up to your main Opera profile root directory. Opera frequently mirrors sync data into your native Bookmarks and BookmarksExtras files.
If your backup folders contain old .ldb files or a larger Bookmarks file from before the crash, close Opera completely and replace your current files with the backup copies.
I hoped this helped you, if did please leave an upvote, I would be really thankful! 😃
Have a nice day!