diff --git a/src/librustdoc/html/static/main.js b/src/librustdoc/html/static/main.js
index 75b0f5df0d8b3..e75b471a8e84f 100644
--- a/src/librustdoc/html/static/main.js
+++ b/src/librustdoc/html/static/main.js
@@ -2422,7 +2422,7 @@ if (!DOMTokenList.prototype.remove) {
             return;
         }
         var crates_text = [];
-        if (crates.length > 1) {
+        if (Object.keys(crates).length > 1) {
             for (var crate in crates) {
                 if (crates.hasOwnProperty(crate)) {
                     crates_text.push(crate);