Animation {0}, whose target visual is {1}, is CPU-bound because of {2}. Go to the Performance Warnings menu in the navigation ...

Animation {0}, whose target visual is {1}, is CPU-bound because of {2}.

Go to the Performance Warnings menu in the navigation toolbar and select the Frames view. Sort the frames by clicking the CPU Time column header and select the frames with the highest CPU time. From the Frames view, select the Visual Tree option and select visual {1}.  From the Frames menu, select the Active Storyboards option and inspect the the animation.