The Previous Cuts are displayed on the Cut Preview as Faded Gray outlines.
These allow you to position the next cut beside a previous cut when cutting several designs from the same mat, such as when /wiki/spaces/FrameShop8x/pages/1942509743the CMC.
This can be turned on/off in the Options menu, and the previous cuts can be cleared from the screen with the Clear Cut History button.
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See: Previous Cuts Toggle
See: Clear Cut History