Hello,
I will try to explain as best as possible: I followed the tutorial for setting up multiplayer in Godot, so I now have a level which loads, which is initially started and owned by the 'host', to which a 'guest' can join.
Im syncing a few properties such as position, playerId, velocity, rotation
The characer.tsn has 2 Camera3d nodes (CameraGame, and CameraCloseUp), with a 3rd camera called Camera3D which is an InterpolatedCamera3D (from here: https://godotengine.org/asset-library/asset/739).
The idea is Camera3D is what is 'used' and it moves between CameraGame and CameraCloseUp for certain events. It works fine in single player.
It works fine when host first starts the game, and it also works fine for the guest who joins.
But once the guest has joined, host seems to lose this camera movement logic, it wouldnt follow the player any more.

Ive got code in the character _ready() func that does the following:
if player == multiplayer.get_unique_id():
$MyCamera.current = true

Infact until I added the below , when the guest joined, host lost ALL its cameras and it went to a static view (which looked like it came from guests initial load position)

func _ready():
	$Camera3D.current = false
	$CameraCloseUp.current = false
	$CameraGame.current = false
	if player == multiplayer.get_unique_id():
		print('set camera plase !!!')
		$Camera3D.current = true
		($Camera3D as InterpolatedCamera3D).target = $CameraGame

With the setting of false, it seems my host is allowed to keep his Camera3D and it follows him again.
However it cant move to $CameraCloseUp.

Is this a misunderstanding on my part of how camera.current - despite being in 2 separate game windows - over rules both instances of the game?
The behaviour im seeing suggests that...
But from a programming POV i find it a bit odd... Do I need to do something a bit more complex to get this to work?

    icecreamant did you check to see if the ID is populating? The logic looks right but it could be that the ID is not populating. May want to debug and check.

      @SnapCracklins yeah I double checked. I can get it working as a Listen Server (so 1 player is hosting, and another joins) but I could only do that by turning off Camera3D in my spawn_player func before adding to the scene, then running the code above.
      However this does not work when running as a Dedicated Server (so 1 headless server, both players join as guest). Same thing happens as before where player 1 joins has correct camera, player 2 joins has correct camera but suddenly player 1's camera becomes player 2's camera and is static

      -- multiplayer.gd
func add_player(id: int):
	print('add_player', id)
	var chara = character_tscn.instantiate()
	chara.player = id
	
	var spawnpoint:Node3D = find_spawn_point(current_level_scene)
	chara.position = spawnpoint.transform.origin
	chara.name = str(id)
	
	# turn off camera when spawning
	chara.get_node('Camera3D').current = false
	
	current_level_scene.get_node('Players').add_child(chara, true)
	

-- character.gd
func _ready():
	if player == multiplayer.get_unique_id() :		
		$Camera3D.current = true
		($Camera3D as InterpolatedCamera3D).target = $CameraGame

      @SnapCracklins ok very interesting. When running as Dedicated Server, both clients who connect - their player id which is set from add_player (which is called from on_connect step of the multiplayer class) is a unique id 123456, however calling multiplayer.get_unique_id() in the _ready() func it is 1 on both clients.
      So my characters spawn and simply given Id 1, theyre not 'told' by the server what their Id should be ? Im not sure..