There are fantastic reasons why it should not be allowed on random local devices, unless the local device is configured with some sort of authentication... but the problem now is that total ban on accessing local devices from a secure web app is a serious choke point for anyone trying to develop something to control appliances outside the walled garden.
Fascinating discussion here with a Plex dev expressing similar frustrations with the general direction of these context barriers... which in their case affects millions of users and threatens to pull down their entire platform. Their solution currently is bizarre; they actually have to hijack DNS resolution and issue SSL certs on the fly for each of their users' servers to allow their web app to connect to a local node. Not possible in my smaller corporate sphere.
Valid question. The devices are in shops all over the country and should be able to run autonomously. I don't want to get into the business of remotely managing those machines, setting up certificates and DNS on each one, especially since I have no control over the routers in the shops. Supporting the app is hairy enough without trying to do tech support for each shop's network issues.
