From al.fre....@gmail.com on August 16, 2013 14:58:16

What steps will reproduce the problem? 1.Open the program, create a new project.
2.Draw anithing.
3.Create a new layer
4.Press TAB key or go to View > Animation Editor to open the Animation Editor.
5.Move the Background cel to the first layer.
6.Now, move the cel of the first layer to the background layer.
7.Press Ctrl + z, or go to Edit > Undo.
8.Error, but the program do not crash What is the expected output? What do you see instead? Well, I think that in this case, undo should do nothing, because when I undo in the step 7, what the program do is move the backgroud cel again into the first layer, leaving the cel on the background layer empty. And that can not be possible. What version of the product are you using? On what operating system? 0.9.5, Windows 7.

Original issue: http://code.google.com/p/aseprite/issues/detail?id=258