Ok. In this case, let's wait for the Qt5 IPR. This is a top priority right now, so I hope to have the first build including this new IPR mode soon.
To be honest, I don't know what is the origin of this problem. This is something that I've never been able to reproduce it here, but probably it is related to the old architecture used by the current raw OpenGL IPR window.
Computer Graphics Software Developer
Octane plugin development and support: LightWave and Houdini