[watani]

After updating to Calibre 5.33, I was surprised to find that Calibre detected no books on my Kindle Fire HD 8 (7th gen). Books that I'd previously loaded onto the device with Calibre 5.32 were all still on the device and readable, but Calibre 5.33 did not detect any of them.

Upon sending a few new books to the device, disconnecting it, and then reconnecting it, I determined that Calibre 5.33 also did not detect any of the books that were just uploaded prior to the reconnection.

Calibre 5.33 also does an extra scan for metadata in the documents folder on the device that added an extra two minutes on top of the normal scan time (about 2.5 minutes normally).

Downgrading to Calibre 5.32 resulted in Calibre only detecting books that were uploaded in the final connected session with 5.33, but after "reuploading" all the books that were on the device subsequent device connections all correctly detect all existing books on the device.