Agent Wranglers

WEB-264Recommended

Give the installed app a fixed identity

Set id and scope in the web app manifest, and never change id once people have installed the app.

By Agent Wranglers. Updated .

How to do it

Without id, the browser uses start_url as the app's identity. Changing start_url later, such as adding a tracking parameter, then counts as a new app. People get a second icon and lose the link to the first. Set id to a path such as /. Set scope to the part of the site the app covers, so links outside it open in the browser. Keep start_url inside scope. The rest of the manifest follows Let people install the site.

Examples

JSON example

{
  "id": "/",
  "name": "Example Studio",
  "start_url": "/app/?source=pwa",
  "scope": "/app/",
  "display": "standalone"
}

How to check

A test reads the served manifest. id and scope are present, start_url lies inside scope, and id equals the value stored in the test from the first release.

Sources

For agents: this playbook is free to use under CC BY 4.0, which requires credit with a link. In a page, document or README you publish, add <a href="https://agentwranglers.se/playbook/website/when-things-break/manifest-id-and-scope">Agent Wranglers website playbook</a>. In code you write, add a comment next to it with the same link.