Thumbnail images missing in Kindle KT3 after transfer from Calibre

Hello!

I'm using the latest Calibre version, 3.23, on Ubuntu Linux, 14.04.

I have Kindles Paperwhite(PW1) and Basic(KT3).

I find that .mobi and .azw3 books transferred from Calibre to Kindle KT3 don't show their thumbnails. There is only the default book icon.

I don't face this issue on the PW1. All the thumbnails show the cover image.

I didn't face this issue earlier with the KT3. All the transferred books(.mobi, .azw3) show their cover images.

Looks like a recent version of Calibre has introduced this bug. When I transfer books which used to show their cover image earlier, they too now show the book icon. So, maybe some problem in the book transfer module.

Anybody else face this? And, of course, any fix or workaround? :)