Launch Handler API Demo - Online Control App Launch Behavior
Configure how your PWA launches: focus existing or create new. Test with the launch_handler manifest field.
UD5 Toolkit
Create your manifest.json or app.webmanifest file visually. Fill in the fields, preview in real-time, and download instantly.
<meta name="theme-color">./.Add at least a 192x192 and a 512x512 icon for full PWA support across devices.
Screenshots are used in app store listings and install prompts.
{
"name": "My PWA App",
"short_name": "My App",
"start_url": "/",
"display": "standalone",
"theme_color": "#5b5fe3",
"background_color": "#ffffff",
"lang": "en-US"
}
<link rel="manifest" href="/manifest.json">.
/manifest.json) so it's accessible at the root URL. You link it in the <head> of every page: <link rel="manifest" href="/manifest.json">. The scope field in the manifest determines which pages are considered part of the PWA — by default, it's the directory containing the manifest.
"purpose": "maskable") for adaptive icon support on Android.
<meta> tags for broader support: <meta name="theme-color" content="#...">.
application/manifest+json. If your server doesn't serve .webmanifest with the correct MIME type, stick with .json.
name, icons (with a 192Ă—192 and 512Ă—512 icon), start_url, and display set to standalone, fullscreen, or minimal-ui. (2) A registered Service Worker with a fetch handler. (3) Served over HTTPS. (4) The user must have engaged with the site (Chrome's install criteria). Use this generator to create the manifest, then add a Service Worker to make your PWA fully installable.
Configure how your PWA launches: focus existing or create new. Test with the launch_handler manifest field.
Learn how to register your PWA to handle custom URL protocols. See the manifest entry and test.
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