diff --git a/Tests/AK/TestURL.cpp b/Tests/AK/TestURL.cpp
index 52024c64a0..97c5541b0f 100644
--- a/Tests/AK/TestURL.cpp
+++ b/Tests/AK/TestURL.cpp
@@ -184,6 +184,12 @@ TEST_CASE(file_url_serialization)
     EXPECT_EQ(URL("file:///my/file#fragment"sv).serialize(), "file:///my/file#fragment");
 }
 
+TEST_CASE(file_url_relative)
+{
+    EXPECT_EQ(URL("https://vkoskiv.com/index.html"sv).complete_url("/static/foo.js"sv).serialize(), "https://vkoskiv.com/static/foo.js");
+    EXPECT_EQ(URL("file:///home/vkoskiv/test/index.html"sv).complete_url("/static/foo.js"sv).serialize(), "file:///home/vkoskiv/test/static/foo.js");
+}
+
 TEST_CASE(about_url)
 {
     URL url("about:blank"sv);