I've been running into lots of issues since I upgraded to 26.5 beta, spotlight doesn't work, mail index was broken and after deleting it I can't reindex my mail., after a while I get an error that reindexing failed and that I should relaunch that app and it will start over. It never succeeds
Looking into the console, it seems that at least the mail issue, but also others system logging errors (trustd, coreduetd) are linked to corrupted sqlite databases.
So I guess the sqlite version is a dud ?