Multiple Background Music for Custom Theme

firesoulgb

firesoulgb

So I wanted to try making my own custom theme for Opera GX, I've been following the tutorials found online, and it's worked except for 1 problem. When I try to add multiple background musics to the theme, it plays all of them together. I have some experience, but definitely not very sufficient, so I'm hoping someone can help me understand and maybe fix the issue.

So far, I've only changed the background music.

{
    "name": "My Theme Test",
    "description": "I'm trying to make a theme",
    "developer": {
        "name": "Fire Soul"
    },
    "icons": {
        "512": "icon_512.png"
    },
    "manifest_version": 3,
    "mod": {
        "license": "license.txt",
        "payload": 
        {
            "background_music":
            [
		"music/DLWinningTheme1.mp3", //Music right here
                "music/DLPlaymakerAndAI.mp3"
            ],
            "browser_sounds":
            
          //A whole bunch of other codes that didn't change
        },
        "schema_version": 1
    },
    "version": "1.0"
}