Point A is interesting because you can see particularly on OSX that it is not native, despite widespread recommendations to use Qt for cross platform developmen

Point A is interesting because you can see particularly on OSX that it is not native, despite widespread recommendations to use Qt for cross platform development. I have used wxWidgets on multiple platforms and despite its idiosyncrasies, I have found it performed very well and is obviously truly native on all platforms (unless you choose wxUniversal as a rendered; nobody does) or unless you do "owner drawn" stuff and paint yourself. In any case I would not hesitate recommending wxWidgets for native controls over Qt. Other minor Qt annoyances include their own scrollbars which ignore the system setting of "jump to where I click the thumb" setting etc.