Working on a tertiary project I ran into how Kirigami.Theme has depreciated colors that aren't documented as such on the apidox. The current discoverability of this is that a user would browse the docs to Theme from the index, start using depreciated colors, get warnings, and only then discover that Kirigami.Theme is attached - probably via this blog post by @mart.
This adds a blurb describing how the property is attached and one should refer to and use PlatformTheme for contemporary color management.
There might be a bug here, though -"Remarks: This component is a singleton" is duplicated when I build this locally and it runs on to the first paragraph. Not sure if its just a quirk in my apidox builder setup.