diff --git a/crates/typst-ide/src/definition.rs b/crates/typst-ide/src/definition.rs
index 69d702b3b..36c06ec6b 100644
--- a/crates/typst-ide/src/definition.rs
+++ b/crates/typst-ide/src/definition.rs
@@ -72,7 +72,8 @@ pub fn definition(
 
         // Try to jump to the referenced content.
         DerefTarget::Ref(node) => {
-            let label = Label::new(PicoStr::intern(node.cast::<ast::Ref>()?.target()));
+            let label = Label::new(PicoStr::intern(node.cast::<ast::Ref>()?.target()))
+                .expect("unexpected empty label");
             let selector = Selector::Label(label);
             let elem = document?.introspector.query_first(&selector)?;
             return Some(Definition::Span(elem.span()));