diff --git a/extensions/firefox/content/PdfJs.jsm b/extensions/firefox/content/PdfJs.jsm
index 8cf7233a8..9bc366dd6 100644
--- a/extensions/firefox/content/PdfJs.jsm
+++ b/extensions/firefox/content/PdfJs.jsm
@@ -173,9 +173,9 @@ var PdfJs = {
 
   updateRegistration: function updateRegistration() {
     if (this.enabled) {
-      this._ensureRegistered();
+      this.ensureRegistered();
     } else {
-      this._ensureUnregistered();
+      this.ensureUnregistered();
     }
   },
 
@@ -188,7 +188,7 @@ var PdfJs = {
       Services.obs.removeObserver(this, TOPIC_PLUGIN_INFO_UPDATED);
       this._initialized = false;
     }
-    this._ensureUnregistered();
+    this.ensureUnregistered();
   },
 
   _migrate: function migrate() {
@@ -307,7 +307,7 @@ var PdfJs = {
     return !enabledPluginFound;
   },
 
-  _ensureRegistered: function _ensureRegistered() {
+  ensureRegistered: function ensureRegistered() {
     if (this._registered) {
       return;
     }
@@ -318,7 +318,7 @@ var PdfJs = {
     this._registered = true;
   },
 
-  _ensureUnregistered: function _ensureUnregistered() {
+  ensureUnregistered: function ensureUnregistered() {
     if (!this._registered) {
       return;
     }
diff --git a/extensions/firefox/content/pdfjschildbootstrap-enabled.js b/extensions/firefox/content/pdfjschildbootstrap-enabled.js
index c228be082..93a748921 100644
--- a/extensions/firefox/content/pdfjschildbootstrap-enabled.js
+++ b/extensions/firefox/content/pdfjschildbootstrap-enabled.js
@@ -27,5 +27,5 @@ Components.utils.import("resource://pdf.js/PdfJs.jsm");
 
 if (Services.appinfo.processType === Services.appinfo.PROCESS_TYPE_CONTENT) {
   // register various pdfjs factories that hook us into content loading.
-  PdfJs.updateRegistration();
+  PdfJs.ensureRegistered();
 }