Recently starting seeing this CORS error on a privately hosted (digitalocean) Discourse installation, only in iOS Safari. It is perhaps causing a failure to render (white screen) on devices with slow connection.
XMLHttpRequest cannot load <discourse_domain>/message-bus/13f8b4fdf79449a2932f19b6bc7d5e97/poll due to access control checks.
(<discourse_domain> is the domain discourse is running on).
There are a few plugins installed on the instance, however the plugins haven’t substantially changed (only stylistically) since the error started appearing.
Any suggestions / hints on how to tackle this would be appreciated!