I just pulled mine up to go through it and if I had to guess I have about 5 read out of probably 250. Which 5 those are, no idea. I also find it very easy to accidentally click on an item, which marks it as read without any visual indication. I just have to know this, and then remember to right-click and mark unread.
I spent a little time this afternoon (maybe 10 minutes) looking at export options to get the data in a way I can go through it. It seems to be stored in a plist along with the bookmarks. plutil has an export option, but it won’t export to json (it throws an error), so I’m left with 150k lines of XML, which then converted to 31k lines of json. I’m now debating if I should continue down this road, or just plow through it in Safari. There are some things on GitHub, but I don’t want to run them without reviewing the code, and at that point, I’d rather write my own. Maybe I’ll use it an excuse to try out duckdb.