diff --git a/components/fonts/font_context.rs b/components/fonts/font_context.rs
index 908d0aba298..212fb587f84 100644
--- a/components/fonts/font_context.rs
+++ b/components/fonts/font_context.rs
@@ -524,7 +524,7 @@ impl FontContextWebFontMethods for Arc<FontContext> {
             });
         }
 
-        font_data.retain(|font_identifier, _| unused_identifiers.contains(font_identifier));
+        font_data.retain(|font_identifier, _| !unused_identifiers.contains(font_identifier));
 
         self.have_removed_web_fonts.store(false, Ordering::Relaxed);