I’m working on an old project running 8.1.48 and ran into a strange SVG render bug on popups where all gradients are rendered in the designer and not rendered at runtime.
Eventually I figured out that I was only seeing this behavior if there were spaces in “Identifier” property on the popup command that opened the popup. I can call the same popup without spaces in the identifier and the SVGs render.
In short, if you are finding that gradients on your SVG are replaced with a black fill on a popup; remove all spaces from the “Identifier” property on your popup command.
I’m just passing this on in hope that someone experiencing this problem will find my post with search and be able to fix this problem.
PS
If anyone is wondering why I used popup command instead of a script. This allows you to do relative positioning.