[Solved] ExtJS: Problem while saving content of textarea (contains HTML tags)

Uncaught SyntaxError: Invalid regular expression: missing /
    at doDecode (ext-all.js:21)
    at Object.decode (ext-all.js:21)
    at Ext.form.Action.Submit.handleResponse (utilities.js:300)
    at Ext.form.Action.Submit.processResponse (ext-all.js:21)
    at Ext.form.Action.Submit.success (ext-all.js:21)
    at o (ext-all.js:21)
    at Ext.data.Connection.s (ext-all.js:21)
    at HTMLIFrameElement.I (ext-all.js:21)
doDecode @ ext-all.js:21
(anonymous) @ ext-all.js:21
handleResponse @ utilities.js:300
processResponse @ ext-all.js:21
success @ ext-all.js:21
o @ ext-all.js:21
s @ ext-all.js:21
I @ ext-all.js:21

({"success":true,"data":{"hasheader":"1","batchsize":"0","delimiter":";","enclosure":"\"","usergroups":"","autousername":"0","setimportmarker":"1","notifyusers":"1","role":"0","mailsubject":"Notification: Your New User Account!","mailbody":"Hello,<br>\r\n<br>\r\nwe'd like to inform you, that your user credentials were imported into our system and a new user account was created for you!<br> \r\n<br>\r\n<strong>Here are your new account credentials:<\/strong><br>\r\n<br>\r\nName: [[+fullname]]<br>\r\nEmail: [[+email]]<br>\r\nYour username: [[+username]]<br>\r\nYour password: [[+password]]<br>","action":"mgr\/settings\/update","file":{"name":"","type":"","tmp_name":"","error":4,"size":0}}}</strong>)

class SettingsUpdateProcessor extends modProcessor {

    public function process() {

        $settings = array(
            'delimiter',
            'enclosure',
            'autousername',
            'setimportmarker',
            'notifyusers',
            'mailsubject',
            'mailbody',
        );

        foreach ($settings as $key) {
            $value = $this->getProperty($key);
            if (isset($value)) {
                $setting = $this->modx->getObject('modSystemSetting', 'userimport.'.$key);
                if ($setting != null) {
                    $setting->set('value', $value);
                    $setting->save();
                } else {
                    $this->modx->log(modX::LOG_LEVEL_ERROR, '[UserImport] SettingsUpdateProcessor: '.$key.' setting could not be found');
                }
            }            
        }
        
        // refresh part of cache (MODx 2.1.x)
        $cacheRefreshOptions = array('system_settings' => array());
        $this->modx->cacheManager->refresh($cacheRefreshOptions);

        $response['success'] = true;
        $response['data'] = $this->getProperties();
        
        return $this->modx->toJSON($response);
    }

}
return 'SettingsUpdateProcessor';

{
                xtype: 'textarea'
                ,name: 'mailbody'
                ,id: 'mailbody'
                ,growMin: 250
                ,grow: true
                ,fieldLabel: _('userimport.notification_template_mail_body')
                ,description: MODx.expandHelp ? '' : _('userimport.notification_template_mail_body_desc')
                ,anchor: '100%'
            }

(..........</strong>)

<i>Hello</i>,<br><br>we'd like to inform you,

<i>Hello</i>,<br><br>we'd like to inform you that the correct syntax is<code>& lt;p class="paragraghClass"& gt;My Content & lt;/p>,

document.getElementById("mailbody").value = myNewContent;
//or
Ext.get("mailbody").set({value: myNewContent}); 
//or
Ext.get("mailbody").dom.value = myNewContent;

document.getElementById("mailbody").value = myNewContent.replace(/(?:<)/g, "&lt++;"); //snuff out all opening angle brackets

if ($setting != null) {
  if($setting == "mailbody"){
    $value = str_replace("&lt++;", "<", $value); //remove your custom entity
  }
  $setting->set('value', $value);
  $setting->save();

unset ($response['data']['mailsubject'], $response['data']['mailbody']);

class SettingsUpdateProcessor extends modProcessor {
 
    public function process() {
 
        $settings = array(
            'delimiter',
            'enclosure',
            'autousername',
            'setimportmarker',
            'notifyusers',
            'mailsubject',
            'mailbody',
        );
 
        foreach ($settings as $key) {
            $value = $this->getProperty($key);
            if (isset($value)) {
                $setting = $this->modx->getObject('modSystemSetting', 'userimport.'.$key);
                if ($setting != null) {
                    $setting->set('value', $value);
                    $setting->save();
                } else {
                    $this->modx->log(modX::LOG_LEVEL_ERROR, '[UserImport] SettingsUpdateProcessor: '.$key.' setting could not be found');
                }
            }            
        }
         
        // refresh part of cache (MODx 2.1.x)
        $cacheRefreshOptions = array('system_settings' => array());
        $this->modx->cacheManager->refresh($cacheRefreshOptions);
 
        $response['success'] = true;
        $response['data'] = $this->getProperties();
        unset ($response['data']['mailsubject'], $response['data']['mailbody']);

        return $this->modx->toJSON($response);
    }
 
}
return 'SettingsUpdateProcessor';