Multiple fatal errors

Problem/Motivation

After installation of this module:

First fatal error:
*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.p

After uninstalling this module using composer, anothe fatal error:
*Drupal\Component\Plugin\Exception\PluginException*: Plugin (filter_link_title) instance class "Drupal\linktitle\Plugin\Filter\FilterLinkTitle" does not exist. in *Drupal\Component\Plugin\Factory\DefaultFactory::getPluginClass()* (line *97* of *core/lib/Drupal/Component/Plugin/Factory/DefaultFactory
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