About Dynamic Edit Mode
You can use the Dynamic Edit mode to change a feature dimension, move a feature sketch, or move a sketched entity without leaving the graphics window. The model incrementally updates while you are editing. Dynamic Edit is available for features that contain handles for dragging.
Click > > 
Auto Regenerate to activate Dynamic Edit mode.
Auto Regenerate to activate Dynamic Edit mode. | • Dynamic Edit is unavailable for failed features and their child features. • Dynamic Edit is unavailable if the Part has ungenerated features. |