diff --git a/b2g/chrome/content/devtools.js b/b2g/chrome/content/devtools.js
index 921eecf724b..1d3090b0ca5 100644
--- a/b2g/chrome/content/devtools.js
+++ b/b2g/chrome/content/devtools.js
@@ -141,7 +141,7 @@ let developerHUD = {
       delete target.metrics;
       target.display();
 
-      this._target.delete(frame);
+      this._targets.delete(frame);
     }
   },