TypeError: Cannot read properties of null (reading 'width' & 'uvsFloat32')

Referring to this post: “Https://discourse.psychopy.org/t/typeerror-cannot-read-properties-of-null-reading-width/26655

I have encountered the same problem:
“TypeError: Cannot read properties of null(reading ‘width’)” as well as getting "TypeError: Cannot read properties of null (reading ‘uvsFloat32’).

I changed the opacity like it was recommended in the post I’m referring to. But the problem still appears randomly (some participants get the error some don’t). I would really appreciate some help. Thank you!

I have attached the Pavlovia URL of the experiment: It is basically 4 parts but you should be redirected to the next part:


I have also attached the gitlab for each of the parts: