Bluring title bars can be accomplished in WindowBlinds. Curtains can blur explorer backgrounds. Can't blur just be added for explorer titlebars? Even if it isn't all title bars, but just limited to explorer, that would be better than nothing.
As mentioned by Neil the main Dev for Windowblinds and Curtains above, there is OS limitation due to compatibility issue. As a Skin designer myself, I also wish this can be done. But, looking at things, if it can be done, it would have be done long ago. We can have blur in Windowblinds since Windowblinds was design differently than Curtains. The WB skin engine work differently, hence it can skin alot more area compared to Curtains. But, Windowblinds lost a lot of compatibility with lot of Application especially those that come under universal application. These application handled better with Curtains, but, Curtains lost lot of area that can not be skin. So these are the trade off.
Thank you,
Basj,
Stardock Community Assistant