davidfor: Thanks, I know this, and I also asume it should cause no problem, it worked on 3.5.0, but on 3.8.0 and 3.11.0 after copying many new books (factory reset

) the device reads all my books, then I get an empty library. After reboot it reads every title correctly, without collections information. And in some of the cases the database gets corrupt, and in case of trying to repair it, all information is deleted, the only viable solution is putting back the backup. (Strange is, I just re-checked it, and saw even loading book information after reboot, my collections are there. So currently I have no problem

)
Koreader and others: I use Save to disc for these books to a hidden folder, as with 7 thousand books the search feature is anyway slow. But in 3.11 the epub reader seems quicker, with the patch quite useable, only highlighting is painfully slow, so I returned to stock reader it seems

.