No Initial Animation
Some developers want to play different animation or no animation the first time Content is set. This may due to loading remote data or just a matter of graphic, animation or interaction design. You could easily achieve that by setting different transition on interrupted or completed. For example you could set the initial duration of a transition to be 0:0:0 like this in XAML:
And then in code behind set the duration to a reasonable time span after the first content appears: