This isn’t a bug, but an inconvenience:
When in a Social match, if you hit the “Menu” button, it doesn’t show players in the lobby, it just shows the main menu.
In GOW4, hitting the “Menu” button in a Social match would show you all players in the lobby. This was useful for when you join a Social match that only has 3 players in-game, and you want to decide whether you should stay or find a more populated lobby. Many times others join around the same time as you and are also waiting to spawn in, the “Menu” button was great for that in GOW4.
Hopefully in the actual full version of Gears 5, you can still see who is in a lobby of a Social match with the “Menu” button, rather than just the main menu.
I also agree with others saying it’s way too easy to quit matchmaking in Social of Gears 5 Tech Test, you just tap “X” once and you’re out. You could be looking at stats from the last game, and mistakenly hit X twice, and you’re out of matchmaking. It should either ask you if you want to quit when you hit “X”, or you hold “X” to quit or something else.