: The 125-person capacity is not an official feature. It is a "hack" or patch that exploits a vulnerability in the game's configuration to increase the maximum slot count.
: For a player to even see or join a server with more than 8 slots, they must have the same patch or configuration change applied locally. Otherwise, the server will not appear in their session list. Technical Setup & Configuration ETS2 – Servidor de 125 pessoas 1.44.1.9 1.44
To enable or find these servers, players typically perform a manual configuration tweak: : The 125-person capacity is not an official feature