Repro steps:
1. Open "Canvas.zip" project;
2. Open "scene" scene;
3. From the Assets folder drag the object "DragMe" on Canvas in the hierarchy;
note: you might need to do the 3rd step more than once
GIF attached

Actual behavior: "DragMe" object is invisible the first time it is dragged on Canvas.
Expected behavior: Image should be visible

Reproduced on: 5.4.0f3, 5.5.0a5
Didn't reproduce on: 5.3.6p2