Error: tenants is null

[nfriedly]

I was trying to figure out what was wrong with my app's Deploy to Azure button, because I kept getting "Error: tenants is null" in the console, then I tried the button on the example here and got the same error.

Not sure if it's a problem in the azuredeploy.json or on the Azure side, although I tried my app without any azuredeploy.json and got the same error, so I think it's more likely on the Azure side. Just not sure who to tell about it there.