Display an error when clicking disabled link to register protocol handler (#6079)

CHANGELOG

@@ -1,6 +1,7 @@
 CHANGELOG Roundcube Webmail
 ===========================
 
+- Display an error when clicking disabled link to register protocol handler (#6079)
 - Add option trusted_host_patterns (#6009, #5752)
 - Support SMTPUTF8 and relax email address validation to support unicode in local part (#5120)
 - Support additional connect parameters in PostgreSQL database wrapper

program/js/app.js

@@ -9473,7 +9473,10 @@ function rcube_webmail()
     var nav = window.navigator;
 
     if (!nav || (typeof nav.registerProtocolHandler != 'function')) {
-      $(elem).addClass('disabled').click(function(){ return false; });
+      $(elem).addClass('disabled').click(function() {
+        ref.display_message(ref.gettext('nosupporterror'), 'error');
+        return false;
+      });
     }
     else if (typeof nav.isProtocolHandlerRegistered == 'function') {
       var status = nav.isProtocolHandlerRegistered('mailto', this.mailto_handler_uri());

program/localization/en_US/messages.inc

@@ -216,3 +216,4 @@ $messages['clicktoresumesession'] = 'Click here to resume your previous session'
 $messages['errcomposesession'] = 'Compose session error';
 $messages['errcomposesessionexplain'] = 'Requested compose session not found.';
 $messages['clicktocompose'] = 'Click here to compose a new message';
+$messages['nosupporterror'] = 'This feature is not supported by your web browser.';

program/steps/settings/edit_prefs.inc

@@ -42,7 +42,7 @@ function rcmail_user_prefs_form($attrib)
     global $RCMAIL, $CURR_SECTION, $SECTIONS;
 
     // add some labels to client
-    $RCMAIL->output->add_label('nopagesizewarning');
+    $RCMAIL->output->add_label('nopagesizewarning', 'nosupporterror');
 
     unset($attrib['form']);