Thanks, merged!
Always composite image to account for alpha transparency
Merged; thanks!
I think my preference would be to remove xzgv's "native" thumbnail functionality altogether. Neither zgv nor xv seems to be maintained, and neither is in Debian, so cooperation with other apps is no longer a feature. This leaves "standalone thumbnails not depending on DBus". I did have a look to see if there was a standalone implementation of the standard (i.e. in a library) that doesn't require DBus; but I can't find such a thing. Or does e.g. Nautilus or Dolphin update thumbnails? Does any standalone...
Merged, thanks!