Comment 11 for bug 1296777

Sofar I could narrow this regression down to an issue related to UbuntuShape. If it's UbuntuShape itself, a regression in Qt 5.2 in combination with UbuntuShape or just Qt 5.2 itself I'm still figuring out.

For the time being - until it is fixed for real - you can use the "x-canonical-non-shaped-icon" as a work-around to correct the rendering of the avatar-icons right now. This hint is actually meant to allow an application to avoid masking the icon (e.g. SVGs, PNGs with alpha) with the UbuntuShape.

In C/C++ code do...

notify_notification_set_hint (notification, "x-canonical-non-shaped-icon", g_variant_new_string ("true"));

... to set said hint. Do that after notify_notification_new(...) but before notify_notification_show (...)