link to contact in a custom field of campaign is missing CID parameter

[zfranque]

my steps:

1. I go to the campaign dashboard, click on "view" of a campaign.
2. In the overview I click on a contact which is referenced in a custom field of the campaign.
3. The link leads to nowhere because the CID ist missing.

The link looks like this: https://XXX/civicrm/contact/view?reset=1&cid=

Thanks in advance!

CiviCRM 5.35.2 Drupal 7.82 de.systopia.campaign 1.2