I was working on a project (which was working) and today I got this error
loading the model gets an error but it still appears in the scene, but I get an error trying to access the model’s mesh Instances.
I think is a problem with the browser, I’ve tried it with firefox and I don’t get this error
I can’t reproduce locally here on my end.
Can you try in an incognito tab and see if you still get the same issue?
it works in the incognito tab, I think it’s the browser, I’ve tried to clean the cookies and the cache but I still get the errors. I don’t know 
I’m working on firefox now.
Also, I commented this to my work colleagues and it seems to be something wrong with chrome because Twitch and Twitter are not working for them either, but in the incognito tab it does.
Could be related to any extensions that are installed if incognito works.