What toJSON returns and ChartState.drawings carries. Versioned so a 1.9.x save (a bare Drawing[]) is recognisable and upgraded rather than misread.
toJSON
ChartState.drawings
Drawing[]
What
toJSONreturns andChartState.drawingscarries. Versioned so a 1.9.x save (a bareDrawing[]) is recognisable and upgraded rather than misread.