diff --git a/spec/formatting.md b/spec/formatting.md
index 6d1b1746a5..d45f7b557b 100644
--- a/spec/formatting.md
+++ b/spec/formatting.md
@@ -395,13 +395,17 @@ For each _option_:
    1. Let `id` be the string value of the _identifier_ of the _option_.
    1. Let `rv` be the _resolved value_ of the _option value_.
    1. If `rv` is a _fallback value_:
-      1. If supported, emit a _Bad Option_ error.
+      1. Emit a _Bad Option_ error, if supported.
    1. Else:
       1. If the _option value_ consists of a _literal_:
          1. Mark `rv` as a _literal_ _option value_.
       1. Set `res[id]` to be `rv`.
 1. Return `res`.
 
+> [!NOTE]
+> If the _resolved value_ of an _option value_ is a _fallback value_,
+> the _option_ is intentionally omitted from the mapping of resolved options.
+
 The result of _option resolution_ MUST be a (possibly empty) mapping
 of string identifiers to values;
 that is, errors MAY be emitted, but such errors MUST NOT be fatal.