Tested and confirmed on my machine. We'll see if we can get this fixed up for the next version. In the meantime, you can create a Compatibility rule for Avast and adjust the TitleBar Button vertical and horizontal offsets manually for it.
More info here: http://www.displayfusion.com/Help/#settings-compatibility
Just wanted to follow-up and let you know that we've released DisplayFusion 3.4.1 Beta 1, which should resolve this issue. You can download the beta version using the link below:
