4 players only as that is also the limit in 5e.
However you dont need a healer or a rogue for heals / traps / locks, so you can play with any 4 characters, one just needs to be Dex based for sleight of hand. Food / Potions for healing.
O_o
There is no player limit in 5th edition.
Anyway, Swen mentioned an Iron Man mode being in the works for the future. They intentionally made the UI as such that the party size can be expanded through mods. This probably won’t increase the player cap for multiplayer unless somebody gets private servers to host the game running.