The user-entered string '[social_event:enrolled_event_url]' must begin with

Problem/Motivation

I'm not sure what caused this yet, but It probaby is a module thats not part of OS. I installed a number of addtional modules.

The site is inaccessible, all pages show:
InvalidArgumentException: The user-entered string '[social_event:enrolled_event_url]' must begin with a '/', '?', or '#'. in Drupal\Core\Url::fromUserInput() (line 216 of core/lib/Drupal/Core/Url.php).

Steps to reproduce

Doing some debugging now, but if someone can already identify the issue, let me know, thanks.