@Huaiwei_Sun I can confirm that the problem persists with ray 2.5.0: Exposing ports and mapping them outside of the docker results in “The connection was reset” in Firefox. The problem also persists when installing the optional dependencies for the dashboard. Interestingly enough, the problem is solved when using the --network host flag in docker run, but that is applicable only in very specific cases.
This answer from SO suggests that it might have to do with the HTTP server technology/isolation level, but I have nearly 0 knowledge on the subject.