I’m trying to get application windows to be “transparent with blurred background while moving”, but so far I have only managed to get the transparency to work. I have enabled “Translucency” and “Blur” as follows:

I noticed that Konsole has a specific setting for “Blur background” and after enabling this I get the desired effect (but it only works in Konsole):
Any idea on how to get transparency + blur while moving…?