When In-Portal have not any enabled theme (and set primary) there no any error message, just blank page without text. Also debugger is not loaded.
Guess there must be something that leads user to problem.
During debugging I found that application interrupts on it's init. Further debugging showed that problem is in that method:
core/kernel/application.php
/**
* Stops processing of user request and displays given message
*
* @param string $message
* @access public
*/
public function ApplicationDie($message = '')
{
$message = ob_get_clean() . $message;
if ( $this->isDebugMode() ) {
$message .= $this->Debugger->printReport(true);
}
echo $this->UseOutputCompression() ? gzencode($message, DBG_COMPRESSION_LEVEL) : $message;
exit;
}
Output of this code will be done in buffer and never be showed.