@SweetP wondering if you've figured out where the sessions are stored post Mojave? I'm in the same predicament as Arlo - can't find my backed up plist files to extract sessions from.
I tried your suggestion of .../safari/extensions.plist and that didn't work for me.
I replied to your other thread.
The old javascript version of SessionRestore (the version you have) isn't being supported anymore. It has been deprecated in macOS Catalina
That would be fantastic!
Not sure how difficult it is or would be to include similar functionality as the Chrome "Session Buddy" extension has, but that one is nearly perfect. Just food for thought 🙂
PS: Since there is literally nothing else available on the market for Safari, I'm sure there is demand and willingness to accept a price tag.