diff --git a/web/password_prompt.js b/web/password_prompt.js
index 2a2db4e6e..8730ba996 100644
--- a/web/password_prompt.js
+++ b/web/password_prompt.js
@@ -60,7 +60,6 @@ class PasswordPrompt {
 
   open() {
     OverlayManager.open(this.overlayName).then(() => {
-      this.input.type = 'password';
       this.input.focus();
 
       var promptString = mozL10n.get('password_label', null,
@@ -78,7 +77,6 @@ class PasswordPrompt {
   close() {
     OverlayManager.close(this.overlayName).then(() => {
       this.input.value = '';
-      this.input.type = '';
     });
   }
 
diff --git a/web/viewer.html b/web/viewer.html
index 766fc2b47..d08f6392e 100644
--- a/web/viewer.html
+++ b/web/viewer.html
@@ -307,8 +307,7 @@ See https://github.com/adobe-type-tools/cmap-resources
               <p id="passwordText" data-l10n-id="password_label">Enter the password to open this PDF file:</p>
             </div>
             <div class="row">
-              <!-- The type="password" attribute is set via script, to prevent warnings in Firefox for all http:// documents. -->
-              <input id="password" class="toolbarField">
+              <input type="password" id="password" class="toolbarField">
             </div>
             <div class="buttonRow">
               <button id="passwordCancel" class="overlayButton"><span data-l10n-id="password_cancel">Cancel</span></button>