Here is the base version of the Overwolf manifest.json file:

manifest.json

{
    "manifest_version": 1,
    "type": "WebApp",
    "meta": {
        "name": "Demo_App",
        "version": "1.0.0",
        "author": "Developer_Name",
        "icon": "IconMouseOver.png",
        "icon_gray": "IconMouseNormal.png",
        "description": "Demo App"
    },
    "data": {
        "start_window": "MainWindow",
        "windows": {
            "MainWindow": {
                "file": "Files/index.html",
                "transparent": true,
                "resizable": true,
                "size": {"width": 400, "height": 300},
                "min_size": {"width": 200, "height": 200},
                "max_size": {"width": 600, "height": 500}
            }
        }
    }
}