Elm update infinite loop - elm

Question

New to Elm, so I may be missing something obvious.
I'm working on an Elm application that uses annaghi/dnd-list. I'm encountering an infinite loop of calls to update. This happens when clicking on one element, then another one. Here's the code:
config : DnDList.Config Player
config =
{ beforeUpdate = \_ _ list -> list
, movement = DnDList.Free
, listen = DnDList.OnDrag
, operation = DnDList.Swap
}
system : DnDList.System Player Msg
system =
DnDList.create config DndMsg
type alias Model =
{ navKey : Nav.Key
, room : WebData Room
, dnd : DnDList.Model
, startError : Maybe String
}
type Msg
= RoomReceived (WebData Room)
| DndMsg DnDList.Msg
...
update : Msg -> Model -> ( Model, Cmd Msg )
update msg model =
case msg of
RoomReceived room ->
( { model | room = room }, Cmd.none )
DndMsg message ->
let
room = model.room
in
case room of
RemoteData.Success actualRoom ->
let
( dnd, players ) =
system.update message model.dnd actualRoom.players
updatedRoom = RemoteData.map
(\roomData ->
{ roomData | players = players }
) room
in
( { model | dnd = dnd, room = updatedRoom }
, system.commands model.dnd
)
_ ->
( model, Cmd.none )
When I change the line system.commands model.dnd to Cmd.none, then there is no infinite looping call to the update function, but also nothing happens. The message that keeps getting called in the dnd-list library is GotDropElement (Ok dropElement)
Again, new to Elm, so this may be a poorly formed question, but any help is appreciated.
Thanks!

Answer 1

Figured it out. Had to add a subscription to listen to mouse events
currentSubs : Model -> Sub Msg
currentSubs model =
case model.page of
GameRoomPage pageModel ->
GameRoom.subscriptions pageModel
|> Sub.map GameRoomMsg
_ ->
always Sub.none model
...
main : Program () Model Msg
main =
Browser.application
{ view = view
, init = init
, update = update
, subscriptions = currentSubs
, onUrlRequest = LinkClicked
, onUrlChange = UrlChanged
}

Answer 2

Try following the flow from system.commands. Probably it is eventually sending again the message DndMsg and this is what is causing the issue.
It is usually considered not a good practice to send messages from commands.
In case you cannot solve the issue, having a working example of the problematic code in Ellie (https://ellie-app.com/new) would help.