I think the subject of this post pretty much explains my frustration. I have attached a video of the issue to show what I am experiencing. There may be a good explanation for this. But I haven't found one and it is really frustrating me. I am trying to cut the difference of a shape to the exact edge of a circle. But it is impossible since the difference boolean moves the paths. BTW: the original shape does not disappear because I duplicated it before performing the boolean operation.

A circle will become a 4-node path when used in a boolean. As you have discovered, a 4 node cubic Bezier path cannot replicate a circle with precision.

It is suggested to use instead of a circle, a 36 or 72 node polygon, convert to path and change the cusp nodes to smooth. After that, perform the boolean ops.

Thank you. I will try that. Since circles are a major shape in Inkscape and booleans are a primary function, perhaps the code should convert a circle into something more than a 4 node bezier when a boolean is applied. Thank you for your input.

That was the answer. You are a wizard. The polygon gave me no problems.