[BetterRed]

ninja'd

As I said

Originally Posted by BetterRed

Also check that you're not using any of the packages mentioned in calibre freezes/crashes occasionally?.

In there you'll find this

There are several possible things I know of, that can cause this:
...

• You are using a Wacom branded USB mouse. There is an incompatibility between Wacom mice and the graphics toolkit calibre uses. Try using a non-Wacom mouse.

...

I'm surprised you've gotten away with using the Wacom Tablet at all, they've been a 'known problem' for calibre (Qt I think) for quite some time. Although i note the tablet specifically is no longer mentioned in the FAQ only the mouse.

BR