Get "You must be connected to wifi to play with your friends".

^{[Mojang] Mega_Spud (Jay Wells):}
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Remove the server you want to play from the server tab add the ip and port once again but don't save it and just tap play.
You have to do it every time you want to play
Featured servers won't work this way.
Workaround for realms:

Locate your realms invite link and join from there
https://realms.gg/xxxxxxxxxxxx - just an example link

_{workarounds found by TeCH ZerO 7 and RDeckard}