GeoJSON feature properties as nested array returned as String literal of "object Object" on map click event

[antonhalim]

Hi! I am currently using mapbox-gl with GeoJSON feature property as an array of objects, eg:

{
    geometry: {
        type: "Point",
        coordinates: [-120.613731, 35.115046]
    },
    properties: [
        {report_id: 1},
        {user: 1},
        {age: 42]
    ]
}

The reason I'm doing this is to get an ordered tooltip data from the properties.

this.map.on("click", (event)=>{
                const features = this.map.queryRenderedFeatures(event.point, {layers: ['metrics-points']})
                if(_.isEmpty(features)) return

                const feature = features[0]
                console.log(feature.properties)
            })

I'm getting a result of Feature Object with properties of

Object
0: "[object Object]"
1: "[object Object]"
2: "[object Object]"

instead of what I expect, which is

properties: [
        {report_id: 1},
        {user: 1},
        {age: 42]
    ]

My guess, map feature layers doesn's support nested feature properties.
Any idea how can I get get the string object literal being converted as object instead of string?
I shared a jsbin how my code should looks like here https://jsbin.com/migoqanoga/1/edit?html,js,output
Thank You!

[jfirebaugh]

Duplicate of #2434.