pwa.rocks | A selection of Progressive Web Apps | Frontend Framework library

There are certain spec changes recently. Going ahead, starting from chrome version 68, the developer will have to manually trigger the prompt by capturing the beforeinstallprompt, deferring it if required, and calling prompt() method on it as and when required. More on it can be read from the official document, which states the updated requirements as:

1. The web app is not already installed
2. Meets a user engagement heuristic (currently, the user has interacted with the domain for at least 30 seconds)

3. Meets the Progressive Web App criteria:
   (a) Includes a web app manifest that includes:

   (i) short_name or name

   (ii) icons mustinclude a 192px and a 512px sized icons

   (iii) start_url

   (iv) display must be one of: fullscreen, standalone, or minimal-ui

   (b) Served over HTTPS (required for service workers)

   (c) Has registered a service worker with a fetch event handler

Also, now coming to the second part of why beforeinstallprompt not getting fired and not sending console outputs. The reasons can be:

1. "You can only call prompt() on the deferred event once, if the user dismissed it, you'll need to wait until the beforeinstallprompt event is fired on the next page navigation." So essentially what this might mean is that if you might have cancelled the event or closed the pop up, it might not even get triggered again. AFAIK, there's a cool off period which can go on till 90 days.
2. "If the web app manifest includes related_applications and has 'prefer_related_applications': true, the native app install prompt will be shown instead." There can be a possibility of setting the prefer_related_application flag to true and missing out on mentioning the related_applications tag. Hence, none of the installation prompts might appear.
3. Make sure the you are not testing "A2HS" flow on the desktop (use remote debugging instead). Because as given in this article, "Chrome has a slightly different install flow for desktop and mobile. Although the instructions are similar, testing on mobile requires remote debugging, without it, it will use the desktop install flow." and "For Mac or Windows, you'll need to enable the #enable-desktop-pwas flag".