Error in error.php: Undefined constant "T3_TEMPLATE_PATH"

The standard error.php from uber 3.0.0 throws an error on my site:
Error: Undefined constant "T3_TEMPLATE_PATH"

I had to replace the following line:
<?php if($theme && is_file(T3_TEMPLATE_PATH . '/css/themes/' . $theme . '/error.css')):?>

with:
<?php if($theme && is_file($this->baseurl . '/templates/' .$this->template. '/css/themes/' . $theme . '/error.css')):?>

I can't replicate this error from my end, could you share the URL + super admin + ftp account of your site? I will check for you.

Thank you for this. I ran into the exact same problem. Problem fixed.

torres86 Glad to hear that 😉