diff --git a/src/misc/markdown.rs b/src/misc/markdown.rs
index d82e9a2..df3da6e 100644
--- a/src/misc/markdown.rs
+++ b/src/misc/markdown.rs
@@ -396,7 +396,6 @@ fn check_code<'a>(root: &'a AstNode<'a>, blacklist: &[String]) -> bool {
 fn check_math(html: &str) -> bool {
     let math_detected = Arc::new(AtomicBool::new(false));
 
-    let mut output = vec![];
     let _ = HtmlRewriter::new(
         Settings {
             element_content_handlers: vec![element!("span[data-math-style]", |_| {
@@ -406,7 +405,7 @@ fn check_math(html: &str) -> bool {
             })],
             ..Settings::default()
         },
-        |c: &[u8]| output.extend_from_slice(c),
+        |_: &[u8]| {},
     )
     .write(html.as_bytes());