Working in devMode, when trying to edit an existing single or structure entry, I get an InvalidArgument error
yii\base\InvalidArgumentException: Syntax error. in ...vendor/yiisoft/yii2/helpers/BaseJson.php:133
if (isset($availableErrors[$lastError])) {
throw new InvalidArgumentException($availableErrors[$lastError], $lastError);
}
I notice in Chrome tools I get a bunch of Craft is not defined errors any ideas?