Web app manifest does not meet the installability requirements
Installability is a core requirement of Progressive Web Apps (PWAs). By prompting users to install your PWA, you allow them to add it to their home screens. Users who add apps to home screens engage with those apps more frequently.
A web app manifest includes key pieces of information required to make your app installable.
How the Lighthouse web app manifest audit fails
Lighthouse flags pages that don't have a web app manifest that meets minimum requirements for installability:
If a page's manifest doesn't include the following properties, it will fail the audit:
iconsproperty that includes a 192x192 px and a 512x512 px icon
displayproperty set to
prefer_related_applicationsproperty set to a value other than
A web app manifest is necessary for your app to be installable, but it isn't sufficient. To learn how to meet all the requirements for installability, see the Discover what it takes to be installable post.
In the Lighthouse report UI the full PWA badge is given when you pass all of the audits in all of the PWA subcategories (Fast and reliable, Installable, and PWA optimized).
How to make your PWA installable
Make sure your app has a manifest that meets the criteria above. See Make it installable for more information about creating a PWA.
How to check that your PWA is installable
When your app meets the minimum requirements for installability, Chrome fires a
beforeinstallprompt event that you can use to prompt the user to install your PWA.
Learn how to make your app installable in Chrome with the Make it installable codelab.
In other browsers
Other browsers have different criteria for installation and for triggering the
beforeinstallprompt event. Check their respective sites for full details: