Mimic not working due to SharedArrayBuffer

Last year, I briefly tried the Mimic on my own, and I found it to be a pretty neat tool, but this year I set out to teach a class with it. However, we quickly found that Mimic would not run in recent browser versions. I have Chrome 94, but I also tested Firefox and Edge. This is the error message:
Mimic error: Current environment does not support SharedArrayBuffer, pthreads are not available!
It seems like something related to this SharedArrayBuffer has changed recently as I see here
I can tell that this problem is caused by recent browser updates, since we have some old laptops that hadn’t been turned on all summer and were behind on updates, and it worked fine on them.
So I guess I have three questions.
Is this in fact a problem caused by browser updates?
Can I expect this to be remedied in the near future?
Is there any way to work around this in the meantime?

Thanks for creating what remains an awesome product

Hi Rondnelson.

Unfortunate, it’s up to the browser vendors. Right now 3D mimics only work in Chrome. We hope that Firefox re-enables shared array buffers some day, but we don’t have a timeline for that.

Cheers, Sam.

Thanks Sam, but I was actually trying to use the Mimic on the latest version of Chrome. If all the major browsers no longer support shared array buffers in the way you are using them, does that mean that the 3D mimics are in a state of hiatus for the foreseeable future?

Sharedarrybuffer is definitely still supported as of Chrome 95.0.4638.49.

What version of Chrome are you on? Is this a computer you own, or a school computer?

Edit: re-reading your original post, you do mention a school. We are not affected by cross-origin sharedarraybuffer, everything is same-origin. I am guessing that your school’s IT department has disabled sharedarraybuffer via group policy.

Contact IT and see if they have set registry key SharedArrayBufferUnrestrictedAccessAllowed to dword:00000000. If they have, RMS Mimics will not work.

Thanks for the reply. I’m on chrome 95.0.4638.54 at the moment, but I still get a Mimic error: Current environment does not support SharedArrayBuffer, pthreads are not available!. I’m using my own laptop which has no administrators other than myself, and I haven’t done anything to disable SharedArrayBuffers. This is the project I was working on, but as you can see there’s nothing significant in it now. I’m no expert on the registry, but Computer\HKEY_CURRENT_USER\SOFTWARE\Google\Chrome doesn’t contain any entry called SharedArrayBufferUnrestrictedAccessAllowed. I also tried it on another computer of mine and got the same error. I wonder what could be the difference between your computer/browser/whatever and mine.

Whoops, C++ mimics. I should have guessed. My quick sanity check was on a Blockly mimic, which worked.

This issue does reproduce on my machine. We are now investigating.

Thanks! That’s heartening to see that the problem is reproducible.