PWA app install icons should reflect the configured favIcon

[sleidig]

Design of the platform is now widely configurable (see #1949), including the favicon. However, to support a fully "white-labeled" platform, the app icon (after installing as PWA) and splash screens also need to reflect the custom favIcon.

This needs to reflect in both

• index.html
• manifest.webmanifest
• images need to be available without permissions?

[sleidig]

observations + notes:

PWA Icons:

• webmanifest requires square icons
• it also works with just a single icon file for "sizes": "any"
• a remote path like "src": "db/app-attachments/SiteSettings:global/favicon" seems to work without issues
• there is an open source generator for all icon formats:
  • https://www.pwabuilder.com/imageGenerator / https://github.com/pwa-builder/pwabuilder-Image-Generator
  • https://www.npmjs.com/package/pwa-asset-generator
  • all of these are designed to run during development and edit the index.html before final build time. Probably not suitable to run on a user's client.

Other PWA Settings (name, theme)

• we also have "name" in the manifest that should probably overwritten to the custom site name
• also: theme_color (--> color customized in site settings?)

Possible approaches

• if seems possible to dynamically create a manifest file: https://dev.to/pablo_74/pwa-set-manifest-json-name-icon-dynamically-client-side-jabbadabbadoo-10h7