First I want to thank Kovid Goyal for this great piece of Software.
I'm using calibre portable and since 0.8.44 the E-book Viewer displays epubs and azw in a strange way. Please look at the attached picture. 0.8.45 shows the same behaviour. I just updated and didn't change any settings. Happens with all epubs and one azw i tried.
Is this a bug or am i doing something wrong, maybe a new feature i missed?
Have fun!