Default MDX component overrides passed to MDXProvider by boot. These
are the platform's phantom defaults (MARKDOWN_SYNTAX_SPEC §11.2): they are
always present in the provider — even for a plain-markdown repo that never
calls boot({ mdxComponents }) — so the platform-emitted Admonition (§12)
and WikiLink (§13) components resolve without the MDX missing-reference guard
firing, and Markdown links route in-app via Link. An app overrides any
of them by name via boot({ mdxComponents }), which merges over these
defaults (§11.3) — overriding WikiLink alone still keeps a and Admonition.
Default MDX component overrides passed to MDXProvider by
boot. These are the platform's phantom defaults (MARKDOWN_SYNTAX_SPEC §11.2): they are always present in the provider — even for a plain-markdown repo that never callsboot({ mdxComponents })— so the platform-emittedAdmonition(§12) andWikiLink(§13) components resolve without the MDX missing-reference guard firing, and Markdown links route in-app via Link. An app overrides any of them by name viaboot({ mdxComponents }), which merges over these defaults (§11.3) — overridingWikiLinkalone still keepsaandAdmonition.