Does anyone know why when I run a custom block without screen refresh, my background appears, but with screen refresh it doesn't
The code:

I can get it to work when moving the background block and the erase all block out of the render block, but I would still like to know why it didn't work?

could you link the project?

https://scratch.mit.edu/projects/1375659969/ (I know there's nothing in the list yet)

It's working the way I had it now, I think.

the project draws the light blue background and then the darker background with run w/o screen refresh checked on both blocks

the project still draws both backgrounds when i turn off run w/o screen refresh, although the second darker background draws especially slow

the slowness is due to it using more blocks and a drawing technique requiring 172,800 iterations (loops) instead of 90

one thing you can do to improve the speed is not have pen down pen up in the inner loop, instead put pen down before the outer loop and pen up after it

the following project lists the relative time “cost” for each block in scratch and may be helpful for figuring out which blocks to remove or replace to improve the drawing speed Every block timed v2