TypeError: Cannot read property 'readPixels' of undefined

Coding
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I am trying to run my experiment online. It’s an audio discrimination task. It works perfectly on the Builder and on the Coder. But when I run the experiment online https://pavlovia.org/run/anfelaras/english-listening-task/html/, I get different errors depending on the navigator I’m using.

With Chrome, I get:
Unfortunately we encountered an error:
** TypeError: Cannot read property ‘readPixels’ of undefined *
Try to run the experiment again. If the error persists, contact the experimenter.

With Safari, the page it loads but:
Keys don’t work and the sound does not work.

Here’s a link to my project’s files, I made it public: [Andres Lara / English Listening Task · GitLab] You can run my file English_Perception.psyexp on PsychoPy to see what’s supposed to appear when I run my experiment online.

Here’s a screenshot of the error message I’m getting on chrome:
18

I tried going into the console on chrome to see what the errors were but I think it’s a problem with the underlying script and I don’t know how to fix it
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Please help! Thank you in advance.

1 Like
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Hi, I have been having the same problem. Were you able to resolve it?

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Participants in the US are having the same problem with Chrome and from IExplorer they get stucked in loading the experiment… However, participants in Spain and I can run the experiment online without a problem.

https://run.pavlovia.org/karena/spanish-l2-3/html/

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I’ve also had some participants in a study I ran recently receiving the “TypeError: Cannot read property ‘readPixels’ of undefined” error, but not others. For those who notified me of it, I asked for details of their browser and operating systems, and received the following replies:

Chrome 79.0.3945.130, iMac OS 10.12.6
Chrome on desktop PC
AVG secure browser and Windows
Chrome on Macbook
Chrome and Windows 7

So, it looks like it’s most common with Chrome, though that might just reflect the popularity of Chrome amongst the sample.