thank you, I just tested and it all works fine (but things always work on my machine 
). I will try to contact the subjects who had memory issues to do it again and will report back.
I do want to ask if you have any insights for the 2nd problem that I mentioned before, that is, people report that the screen doesn’t respond when they click buttons (also encountered here). I can only reproduce the issue on my old Mac, using safari 12.1.2, and there were two people using chrome 86 on Mac who also experienced this. No error messages are shown, just nothing happened.