Using Detach Segment on Drag
You can detach the end-points of a segment (line, arc, ellipse, or spline) from other entities it is attached to in a sketch, if dimensions or relations do not prevent dragging.
Detach Segment on Drag is not available in 3D sketches.
Detach Segment On Drag does not delete relations. Delete relations before you drag an entity to detach. See Display/Delete Relations PropertyManager.
To unmerge sketch endpoints with Detach Segment on Drag: