diff --git a/utils/resolve-refs.test.tsx b/utils/resolve-refs.test.tsx
index 9b29330..2df9845 100644
--- a/utils/resolve-refs.test.tsx
+++ b/utils/resolve-refs.test.tsx
@@ -48,4 +48,10 @@ suite("function resolveRefs", () => {
 		resolveRefs(el, "/");
 		assert.deepEqual(el, elFn());
 	});
+
+	test("ignores absolute URIs", () => {
+		const el = <div>Content with <a href="https://example.org/page.html">Link</a></div>;
+		const resEl = resolveRefs(el, "/");
+		assert.equal(el, resEl);
+	});
 });
diff --git a/utils/resolve-refs.ts b/utils/resolve-refs.ts
index d3ea932..7bdba49 100644
--- a/utils/resolve-refs.ts
+++ b/utils/resolve-refs.ts
@@ -26,8 +26,10 @@ export function resolveRefs(node: Node, dir: string) {
 		&& node.attributes.has("href")
 	) {
 		const original = node.attributes.get("href")!
+		if (/^[a-z][a-z+.-]*:/i.test(original)) {
+			// Ignore refs that start with a URI scheme.
 		/* node:coverage ignore next 3 */
-		if (!original.startsWith("/")) {
+		} else if (!original.startsWith("/")) {
 			console.log(`Warning: found relative href to ${original}`);
 		} else {
 			const ref = posix.relative(dir, original);