Constant UNPREFIXED_LEGACY_CLASSES 

pub const UNPREFIXED_LEGACY_CLASSES: &[&str];

Classes in COMPONENTS that deliberately carry no moss- prefix.

Every other entry must be moss--prefixed; every_component_has_a_class_name enforces that and consults this list for the exceptions. The list lives here, beside the table, rather than in the test: an unprefixed class is a decision made when the entry is written, and a reviewer reading the entry has to be able to see that the decision was made. It was in the test file until 2026-08-06, and the split cost a red build — declaring the masthead and nav interior added 21 unprefixed entries whose exemption had to be recorded in a file nobody editing the table had open.

Two families, both emitted for theme parity — themes written against these names predate the moss- convention, so renaming them would break styling moss does not own:

• Obsidian-style callouts (callout, callout-<type>), emitted alongside their moss-callout equivalents.
• The nav interior and article masthead (main-nav, date-line, …).

Prefix matching is deliberate for the callout family only: callout-<type> is an open set that grows with the callout vocabulary. The chrome names are a closed set and are listed exactly, so a typo’d new one still fails.