Well, I spoke about Kobo Desktop, not the internal rendering engine
I noticed some other little problems:
- add a button that changes to "text mode" (currently you can access it holding a word for a while)
- add a "select" button in "text mode", a tool that allow you to choose the start of a text selection with the first click and the end with an hold. It's useful if you want to select many rows and text on different pages too
- if you change the orientation rotating the document by 90°, to return to the previous orientation you must click the rotate button other 3 times. I think it's more useful to have a rotate button that simply toggles between landscape / portrait orientations
- if the orientation is landscape only the document aspect will be changed, so you'll have menus at the left and right of the screen and you must click over the top of the screen to turn page. It would be better if the entire GUI would change orientation
- you can't change orientation in a epub document, so if you have images in the document you can't see them in landscape mode