Block photo background does not work

Hi everyone, I’m Fabrizio and I’m new to this forum.
I downloaded Blocs a few months ago for school, to date I only have one problem:

When I upload a photo as the background of the block I can’t see it in the preview, but in the live execution it does.
How can I solve it?

Thank you all.
MacBook Pro (13-inch, 2019, Four Thunderbolt 3 ports) - MacOS Catalina 10.15.5

This may be a bug, try creating a new bloc and adding the image to the new bloc/background.

I tried it. It doesn’t work…