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‘readPixels’ of undefined when running study online

I have found several posts for the same issue but haven’t located a real solution yet. When collecting data on Prolific for a relatively simple rating task, a considerable number of subjects have reported this issue, with Chrome on both windows machine and Mac. I don’t think there’s anything wrong with the task itself as I have successfully collected many responses. But I would like to know if there’s a way to resolve this issue because it occurs too frequently and is very annoying for participants. My psychopy version is 3.1.0 if that’s helpful.

Thanks in advance.

Could you try installing PsychoPy 2020.1 and exporting your experiment to Pavlovia again? We’ve done quite a bit of work lately on the JS engine, around better timing and better cross-browser compatibility but you need to re-export your script to make the most of this work

Hi Jon:

Thanks for the suggestion. I think you are referring to uninstall my current version and reinstall the 2020.1, not just change version in experiment setting (which I have tried and doesn’t even sync…). My concern is that my tasks will break since a lot has changed between the two versions and I have many code components in my studies, which will be a much bigger problem.

So I am wondering if there’s anything else I can do. According to this post, can Alain back-port the fix of browser compatibility to earlier versions? If not all the way back to 3.1.0, which is the closest version that has been back-ported?

Thank you for all your help.