required keys for A2HS + possible validation

manifest_work.md

can display manifest

• Check for manifest.json or .webmanifest (if served by correct type)

A2HS

• Check for HTTPs
• (maybe check if SW is registered, not required tho)
• check for reqired keys for A2HS
  • background_color
  • display
  • icon (size, src, type)
  • start_url
  • name / short_name

Suggestion for best practice of keys

• name: length of String (if too long, recomment also adding short_name which will be then used on home screen, launcher etc)
• short_name: recomment also using name as this one is displayed in the install prompt and might be easier to understand
• icons: 1 needed including src, size & type (object pattern matching), size of icon should be devidable by 48. Check for type.
• background_color: maybe check for color + bg_color contrast, check if value is correct(hex, rgb, rgba)
• theme_color: same as bg_color
• display: 4 values allowed (fullscreen, standalone, minimal_UI, browser), pattern matching as validation. We should check for restrictions later on for every value.
• description: length?

validation of values

https://searchfox.org/mozilla-central/source/dom/manifest/ValueExtractor.jsm#48,62 (color + language)