I'm working with the Box theme and have multiple layer lists combined into one widget. When the map loads, all layer lists are fully expanded but only the first is visible, and there is no visual indication to the user that there are others (the user would have to collapse the initial layer list to see the heading for the next list, and collapse that to see the next, etc.
What I'm hoping to do is to set the layer list widget to have all of the lists collapsed by default when the map loads, so the user just sees the text heading for each list, and can then expand the list they want.
I've found this old topic, which is close to what I'm looking for: Is it possible to collapse multiple Layer Lists by default?
but that answer was given for the foldable theme, and it doesn't look like I can apply it to the Box theme. Is there similar code I can use with the Box theme to have all layer lists collapsed by default?