Bug with adding drop shadow to Icons

Hi there, I came across another bug.

When I try to add drop shadow to the icon, like this:

https://drive.google.com/open?id=1eL_XObbPzIUI3jC5f1AY_OXtTBjIemGU

I get the following error screen as soon as a click the button:

https://drive.google.com/open?id=1yLug8uj_F_Vq7AbLXbqLG85YB38GFNCS

This does not happen on any of the other settings, nor does it happen on the Box Shadow on the container. Only on the Icon itself.

Best,
Tony