GoogleChrome
content: mention "any maskable" value for `purpose` field in Maskable icons section of 012 Web app manifest
What page(s) need to be updated?
012 Web app manifest > Maskable icons
Why is this update needed?
Despite this mention in Add a web app manifest, in the icons section (which is linked from Resources at the bottom):
To use maskable icons, sometimes referred to as adaptive icons on Android, you'll also need to add
"purpose": "any maskable"to the icon property.
…and the detailed explanation of purpose in MDN > References > Web app manifests > icons > Values (helpfully linked in the Further reading section of Add a web app manifest):
purposecan have one or more of the following values, separated by spaces: […]
maskable: The image is designed with icon masks and safe zone in mind, such that any part of the image outside the safe zone can safely be ignored and masked away by the user agent.any: The user agent is free to display the icon in any context (this is the default value).
…the Maskable icons section of the 012 Web app manifest page does not mention the option of adding both any and maskable, which would seem to be a far more common use case than the separate maskable 512px icon in the code example. At least a sentence mentioning "any maskable" being the better value for an icon that serves both general and maskable purposes would seem to reduce developer confusion and eliminate probable incorrect usage of purpose, or possible unnecessary duplication of icons to satisfy the requirements as currently explained in 012 Web app manifest > Maskable icons.
What's the deadline?
None, but happy to open a PR with this suggested language at the end of the Maskable icons section, immediately before the Icons in Safari section, open to improvement:
If your icon serves general and maskable purposes, you can set purpose to "any maskable"; purpose accepts one or more of monochrome, maskable, or any, separated by spaces. Refer to the MDN Web App Manifest documentation for details.
Is it a hard deadline?
No
