I needed a trapezoid in my chart and when I couldn't find one in the provided shapes I created a custom shape using a Flex Polygon. However I can't find a way to hide or lock the flex points (the purple squares one uses to change the shape). And since I placed the flex points in the corners they now overlap with the edges of the shape so it's hard to resize it without messing up the polygon. This is how it looks:
Is there a way to convert the flex polygon back to a regular polygon or to lock the flex points?