A browser page as an application is convenient since Chrome wraps it in its own window as an application
and stores the last screen location for when it is opened again.
Also the Window is like an application and Alt-Tab allows switching between the
application window and ather applications.
When a self-hosted git server like git.scanframe.com the URL is automatically
modified to https://git.scanframe.com/users/sign_in.
And when an app shortcut is created from that URL a deviation banner is shown for other URLs from the application
which do not contain the initial app URL (https://git.scanframe.com/users/sign_in)
Normally a manifest section is placed in the HTML header for when an application is created for that page/app.
When this is not the case the next javascript adds the manifest to it with a URL of your making.
To allow pasting in the Chrome browser's console (Ctrl+Shift+J) for the first time the command
allow pasteneeds to be entered.
const startUrl = window.prompt("Start App-URL", window.location.href);
const unsanitizedHtmlPolicy = trustedTypes.createPolicy('unsanitizedHtml', {createHTML: (htmlString) => htmlString});
document.head.querySelector(':first-child').insertAdjacentHTML(
'beforebegin',
unsanitizedHtmlPolicy.createHTML(`<link rel="manifest" href='data:application/manifest+json,{"start_url":"${startUrl}"}' />`)
);