Orange on preview side,whats that mean?

Im making 3 squares overlapping the edges so only 1 pass for for 2 squares side. More efficient/quicker is my thought. For some reason though Im getting orange in the preview. What does the orange mean. There is no warning box associated with it. This is the file if it helps to understand what i mean.

Thanks in advance.

I’ve also seen those. If you rotate piece, it shows just on sides of cut. I’ve ignored them in the past and have no problem with the cut. Maybe just some anomaly in Easel.

No one knows what the orange is yet?!