CODE EXAMPLE FOR JAVASCRIPT

manifest.json example

{
    "theme_color": "#333",
    "background_color": "#eee",
    "display": "standalone",
    "scope": "/path/to/project/directory/",
    "start_url": "/index.php",
    "name": "My Project",
    "short_name": "Project",
    "description": "Short description here",
    "icons": [
        {
            "src": "path/to/icon-192x192.png",
            "sizes": "192x192",
            "type": "image/png"
        },
        {
            "src": "path/to/icon-256x256.png",
            "sizes": "256x256",
            "type": "image/png"
        },
        {
            "src": "path/to/icon-384x384.png",
            "sizes": "384x384",
            "type": "image/png"
        },
        {
            "src": "path/to/icon-512x512.png",
            "sizes": "512x512",
            "type": "image/png"
        },
		{
	    	"src": "path/to/maskable_icon_192.png",
	    	"sizes": "192x192",
	    	"type": "image/png",
	    	"purpose": "maskable"
		},
		{
	    	"src": "path/to/maskable_icon_512.png",
	    	"sizes": "512x512",
	    	"type": "image/png",
	    	"purpose": "maskable"
		}
    ]
}