Do you have [newdb] next to version number in the status line - if is so then see
https://www.mobileread.com/forums/sho...d.php?t=218937 - you can read all about it there - if you don't then very odd.
To get the new database back end (which is in test) you must have applied the tweak to turn it on. I imagine the official manual will be updated until when the new features are officially released.
BR