The note added a moment ago sat inside `properties` as
`"_comment_no_vt_tray": "..."`, which declares a property whose schema is a
string - and in draft 2020-12 a subschema has to be an object or a boolean.
It parses as JSON and reads fine, and a strict validator would reject the
whole schema. `$comment` is the keyword for this and belongs beside
`properties` rather than inside it.
Swept the rest of schemas/ for the same shape while here: every other
property value is a real subschema.
octoturge
7a9b19f72a