Use the whole available space in the scalar/vector/matrix/string selectors.
I found the cause of the issue: we were truncating the text ourselves prior to adding the items instead of leaving it up to the
QComboBox's view to take care of it!
I also had to comment out some text which led to an empty scalar near the bottom of the list, because selecting this empty
scalar leads to a crash. But I don't know what the code was meant for. I haven't seen any side effect so I removed it to fix the
crash, but it would be nice if someone could check the side effects.