diff --git a/extensions/firefox/components/PdfStreamConverter.js b/extensions/firefox/components/PdfStreamConverter.js
index 91ef062e6..504fbc47b 100644
--- a/extensions/firefox/components/PdfStreamConverter.js
+++ b/extensions/firefox/components/PdfStreamConverter.js
@@ -377,11 +377,16 @@ ChromeActions.prototype = {
         break;
     }
   },
-  fallback: function(url, sendResponse) {
+  fallback: function(featureId, url, sendResponse) {
     var self = this;
     var domWindow = this.domWindow;
     var strings = getLocalizedStrings('chrome.properties');
-    var message = getLocalizedString(strings, 'unsupported_feature');
+    var message;
+    if (featureId === 'forms') {
+      message = getLocalizedString(strings, 'unsupported_feature_forms');
+    } else {
+      message = getLocalizedString(strings, 'unsupported_feature');
+    }
 
     PdfJsTelemetry.onFallback();
 
diff --git a/l10n/en-US/chrome.properties b/l10n/en-US/chrome.properties
index 0b469195c..e42ac790c 100644
--- a/l10n/en-US/chrome.properties
+++ b/l10n/en-US/chrome.properties
@@ -14,5 +14,6 @@
 
 # Chrome notification bar messages and buttons
 unsupported_feature=This PDF document might not be displayed correctly.
+unsupported_feature_forms=This PDF document contains forms. The filling of form fields is not supported.
 open_with_different_viewer=Open With Different Viewer
 open_with_different_viewer.accessKey=o
diff --git a/web/viewer.js b/web/viewer.js
index 84dd5ea07..be90b1750 100644
--- a/web/viewer.js
+++ b/web/viewer.js
@@ -609,7 +609,7 @@ var PDFView = {
 //    return;
 //  this.fellback = true;
 //  var url = this.url.split('#')[0];
-//  FirefoxCom.request('fallback', url, function response(download) {
+//  FirefoxCom.request('fallback', featureId, url, function response(download) {
 //    if (!download)
 //      return;
 //    PDFView.download();