Load Costume By Data URI

Simply put, I want to load a costume from a data URI:
I wanted to create a list of costumes to export, then export those for a text engine in Scratch.

I tried using cst_load(url), but it doesn't work.

In longer terms,
This is a block that encodes SVG into URI format:

and it should return a centered singular letter/symbol according to the item you set (1 v) to.

Update 6 - Update category due to lack of support.

Looks like it was fixed. Recently, I couldn't do this.

Probably because I added "data://" instead of "data:".