diff --git a/lib/editor/tinymce/adminlib.php b/lib/editor/tinymce/adminlib.php
index 09fcadae85b..36eb494e803 100644
--- a/lib/editor/tinymce/adminlib.php
+++ b/lib/editor/tinymce/adminlib.php
@@ -246,3 +246,30 @@ class tiynce_subplugins_settings extends admin_setting {
         return highlight($query, $return);
     }
 }
+
+class editor_tinymce_json_setting_textarea extends admin_setting_configtextarea {
+    /**
+     * Returns an XHTML string for the editor
+     *
+     * @param string $data
+     * @param string $query
+     * @return string XHTML string for the editor
+     */
+    public function output_html($data, $query='') {
+        $result = parent::output_html($data, $query);
+
+        $data = trim($data);
+        if ($data) {
+            $decoded = json_decode($data, true);
+            // Note: it is not very nice to abuse these file classes, but anyway...
+            if (is_array($decoded)) {
+                $valid = '<span class="pathok">&#x2714;</span>';
+            } else {
+                $valid = '<span class="patherror">&#x2718;</span>';
+            }
+            $result = str_replace('</textarea>', '</textarea>'.$valid, $result);
+        }
+
+        return $result;
+    }
+}
diff --git a/lib/editor/tinymce/lang/en/editor_tinymce.php b/lib/editor/tinymce/lang/en/editor_tinymce.php
index b3c4ee8db36..01448775d17 100644
--- a/lib/editor/tinymce/lang/en/editor_tinymce.php
+++ b/lib/editor/tinymce/lang/en/editor_tinymce.php
@@ -27,6 +27,8 @@
 
 //== Custom Moodle strings that are not part of upstream TinyMCE ==
 $string['availablebuttons'] = 'Available buttons';
+$string['customconfig'] = 'Custom configuration';
+$string['customconfig_desc'] = 'Custom advanced TinyMCE configuration in JSON format, for example: {"option1" : "value2", "option2" : "value2"}. Any options specified here override standard and plugin settings.';
 $string['customtoolbar'] = 'Editor toolbar';
 $string['customtoolbar_desc'] = 'Each line contains a list of comma separated button names, use "|" as a group separator, empty lines are ignored. See <a href="{$a}" target="_blank">{$a}</a> for the list of default TinyMCE buttons.';
 $string['fontselectlist'] = 'Available fonts list';
diff --git a/lib/editor/tinymce/lib.php b/lib/editor/tinymce/lib.php
index 176ff7e7334..6a3c36a8c87 100644
--- a/lib/editor/tinymce/lib.php
+++ b/lib/editor/tinymce/lib.php
@@ -184,6 +184,16 @@ class tinymce_texteditor extends texteditor {
             $params['theme_advanced_buttons1'] = '';
         }
 
+        if (!empty($config->customconfig)) {
+            $config->customconfig = trim($config->customconfig);
+            $decoded = json_decode($config->customconfig, true);
+            if (is_array($decoded)) {
+                foreach ($decoded as $k=>$v) {
+                    $params[$k] = $v;
+                }
+            }
+        }
+
         if (!empty($options['legacy']) or !empty($options['noclean']) or !empty($options['trusted'])) {
             // now deal somehow with non-standard tags, people scream when we do not make moodle code xtml strict,
             // but they scream even more when we strip all tags that are not strict :-(
diff --git a/lib/editor/tinymce/settings.php b/lib/editor/tinymce/settings.php
index 5b16a610de8..1e8d3f4a004 100644
--- a/lib/editor/tinymce/settings.php
+++ b/lib/editor/tinymce/settings.php
@@ -40,7 +40,9 @@ bullist,numlist,outdent,indent,|,link,unlink,|,image,nonbreaking,charmap,table,|
         get_string('customtoolbar', 'editor_tinymce'), get_string('customtoolbar_desc', 'editor_tinymce', 'http://www.tinymce.com/wiki.php/Buttons/controls'), $default, PARAM_RAW, 100, 8));
     $settings->add(new admin_setting_configtextarea('editor_tinymce/fontselectlist',
         get_string('fontselectlist', 'editor_tinymce'), '',
-        'Trebuchet=Trebuchet MS,Verdana,Arial,Helvetica,sans-serif;Arial=arial,helvetica,sans-serif;Courier New=courier new,courier,monospace;Georgia=georgia,times new roman,times,serif;Tahoma=tahoma,arial,helvetica,sans-serif;Times New Roman=times new roman,times,serif;Verdana=verdana,arial,helvetica,sans-serif;Impact=impact;Wingdings=wingdings', PARAM_RAW));
+        'Trebuchet=Trebuchet MS,Verdana,Arial,Helvetica,sans-serif;Arial=arial,helvetica,sans-serif;Courier New=courier new,courier,monospace;Georgia=georgia,times new roman,times,serif;Tahoma=tahoma,arial,helvetica,sans-serif;Times New Roman=times new roman,times,serif;Verdana=verdana,arial,helvetica,sans-serif;Impact=impact;Wingdings=wingdings', PARAM_RAW, 100, 8));
+    $settings->add(new editor_tinymce_json_setting_textarea('editor_tinymce/customconfig',
+        get_string('customconfig', 'editor_tinymce'), get_string('customconfig_desc', 'editor_tinymce'), '', PARAM_RAW, 100, 8));
 }
 $ADMIN->add('editortinymce', $settings);
 unset($settings);