plot() makers disappear from downloaded png/svg

[sffc]

User report:

When I ran the following code and download the resulted figure, markers were disappeared. If I didn't specify colors, it was ok. The attached are appearance on my browser (Chrome) and its downloaded png. Any solutions?

x=-20:20;
y=x.^2;
plot(x,y,'o','Markerfacecolor','r','Color','r');