"copy" mode: Removing frames from a video results in missing reference frames

[Jan Gruuthuse]

Confirmed:
Selecting frame with ">>" or "UP" arrow, selects a  P-FRM, where the cut is actually made.
Cutting at "none selectable ">>" or "UP" arrow P-FRM" will cut at a  ">>" or "UP" selectable P-FRM  before the cutting point.