This is (probably) NOT a Qt bug but it is likely that the issue can be mitigated in Qt. It may be that Qt is not quite satisfying a standard somewhere.

If you place an image onto the clipboard...

QApplication::clipboard()->setImage(*image);

The current UWP App version of OneNote will not allow it to be pasted in. It states...

"Sorry, we couldn't paste the content from your clipboard. Please try copying and pasting it again"

There is nothing wrong with the image on the clipboard: it can be pasted into everything else, including Word, OneNote 2016 and OneNote Online. It seems that OneNote App is looking for a particular format and not finding it.

We have approached Microsoft about this but it is proving hard to get their attention. We are strongly of the opinion that it is OneNote that is at fault here but also believe that solving the problem might be as simple as adding one more format to the mime data (although we have not been able to identify what to add after hours of looking at clipboard spy software). Any thoughts most welcome