What’s the best way to connect my device running Rasplex to a wifi network with a captive portal (e.g. wifi network is open but requires a login after connecting before internet access is granted)?
This isn’t possible, sorry.
Regards
If you can connect to RasPlex via SSH – either directly across the local WiFi network or via another port (e.g. wired Ethernet) – you can use a dynamic tunnel (-D <port_number>) and then proxy your web browser via that tunnel to complete captive portal registration in a way that will register the RasPlex box.
It’s not handy, but it’s better than nothing. An easier option might be to travel with a WiFi repeater w/NAT routing so that RasPlex can join that network and you can use your phone/etc. to register the repeater and everything behind it’s NAT in one go.
Because most of those access points keeps track of you by your MAC you can also boot to raspbian or similar and do the necessary registrations and it should work next time you boot to rasplex.
Another way its just to spoof the mac of the Pi and register for it
