In an editable mesh, each face appears to have a unique set of edges. This is a pain in the back bottom if you want to do something like collect a list of all the edges that border a face selection. In an editable poly you can store your face selection in A, invert it and store that in B , convert both A and B to edge…
Yes, in editable mesh, each face has it's own set of three edges, when you want to get the matching edge of the neighbor face, there's meshop.getEdgesReverseEdge (there's also a code example in the mxs reference). So one way to get the border you wanted (this depends on the use case, of course): selEdges =…