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packages/markdown/remark/src/frontmatter.ts

@@ -10,6 +10,9 @@ export function isFrontmatterValid(frontmatter: Record<string, any>) {
 	return typeof frontmatter === 'object' && frontmatter !== null;
 }
 
+// Capture frontmatter wrapped with `---`, including any characters and new lines within it.
+// Only capture if it exists near the top of the file (whitespaces between the start of file and
+// the start of `---` are allowed)
 const frontmatterRE = /^\s*---([\s\S]*?\n)---/;
 export function extractFrontmatter(code: string): string | undefined {
 	return frontmatterRE.exec(code)?.[1];