diff --git a/lang/en/debug.php b/lang/en/debug.php
index 4159047419e..b03181e5df1 100644
--- a/lang/en/debug.php
+++ b/lang/en/debug.php
@@ -49,6 +49,7 @@ $string['nomodules'] = 'No modules found!!';
 $string['nopageclass'] = 'Imported {$a} but found no page classes';
 $string['noreports'] = 'No reports accessible';
 $string['notables'] = 'No tables!';
+$string['outputbuffer'] = 'Output buffer';
 $string['phpvaroff'] = 'The PHP server variable \'{$a->name}\' should be Off - {$a->link}';
 $string['phpvaron'] = 'The PHP server variable \'{$a->name}\' is not turned On - {$a->link}';
 $string['sessionmissing'] = '{$a} object missing from session';
diff --git a/lib/outputrenderers.php b/lib/outputrenderers.php
index 3901907b466..0f309bf6408 100644
--- a/lib/outputrenderers.php
+++ b/lib/outputrenderers.php
@@ -2809,16 +2809,20 @@ EOD;
         $output .= $this->box($message, 'errorbox alert alert-danger', null, array('data-rel' => 'fatalerror'));
 
         if ($CFG->debugdeveloper) {
+            $labelsep = get_string('labelsep', 'langconfig');
             if (!empty($debuginfo)) {
                 $debuginfo = s($debuginfo); // removes all nasty JS
                 $debuginfo = str_replace("\n", '<br />', $debuginfo); // keep newlines
-                $output .= $this->notification('<strong>Debug info:</strong> '.$debuginfo, 'notifytiny');
+                $label = get_string('debuginfo', 'debug') . $labelsep;
+                $output .= $this->notification("<strong>$label</strong> " . $debuginfo, 'notifytiny');
             }
             if (!empty($backtrace)) {
-                $output .= $this->notification('<strong>Stack trace:</strong> '.format_backtrace($backtrace), 'notifytiny');
+                $label = get_string('stacktrace', 'debug') . $labelsep;
+                $output .= $this->notification("<strong>$label</strong> " . format_backtrace($backtrace), 'notifytiny');
             }
             if ($obbuffer !== '' ) {
-                $output .= $this->notification('<strong>Output buffer:</strong> '.s($obbuffer), 'notifytiny');
+                $label = get_string('outputbuffer', 'debug') . $labelsep;
+                $output .= $this->notification("<strong>$label</strong> " . s($obbuffer), 'notifytiny');
             }
         }