Vertical size of characters in the Alignment Editor

The vertical size of characters in the Alignment Editor depends on zoom and the font of the characters. However, even when the characters are not visible, it can be made less than some fixed size, which is rather big.

It might be better to be able to decrease the vertical size somehow, as it also reflects the possibility to export the image of the alignment. An alignment can only be exported to a raster format, when the size of the image is less than 32768 x 32768.