diff --git a/resource/concurrent-caller.js b/resource/concurrent-caller.js
index 3110d8a91..66a92f534 100644
--- a/resource/concurrent-caller.js
+++ b/resource/concurrent-caller.js
@@ -26,7 +26,7 @@
 EXPORTED_SYMBOLS = ["ConcurrentCaller"];
 Components.utils.import("resource://zotero/q.js");
 
-f/**
+/**
  * Call a fixed number of functions at once, queueing the rest until slots
  * open and returning a promise for the final completion. The functions do
  * not need to return promises, but they should if they have asynchronous