id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
305	Application icon is unavailable in (e.g.) MessageBox::about() when ICO is used.	Alex Taylor		"QIcon apparently does not support the OS/2 Icon format. (This is not really surprising.)  However, relying on an Icon resource in a .RC allows the application icon to use a proper OS/2 multi-image icon to be used, which is nice. Presumably this is because the OS handles the rendering and not Qt.  

However, doing it this way appears to mean that Qt cannot access the application icon for other purposes.

In particular: creating an 'about' dialog with `QMessageBox::about()` is supposed to (according to the Qt4 docs) use the application or parent widget's icon if it exists, or use the generic Information icon otherwise.
However, the actual result in this case is no icon at all.  I assume this is because Qt4 'knows' there's an application icon, so it doesn't fall back to the Information icon... but the application icon is in a format it can't draw, so it ends up drawing nothing.

I assume other contexts would also be unable to render the application icon.  If support for OS/2 Icon cannot easily be added, perhaps the failure logic could be improved."	defect	closed	trivial	Qt 5	General	4.7.3	low	wontfix