What drawing:change reports happened to the listed ids. The list is empty for a step of the undo history that changed no drawing, a study input anchor's drag and its undo or redo, so a control showing whether Undo is available still refreshes.
drawing:change
What
drawing:changereports happened to the listed ids. The list is empty for a step of the undo history that changed no drawing, a study input anchor's drag and its undo or redo, so a control showing whether Undo is available still refreshes.