Oops, an error occurred!
The argument "image" was registered with type "object", but is of type "integer" in
view helper "TYPO3\CMS\Fluid\ViewHelpers\ImageViewHelper".
<f:image image="{contact.photo.uid}" alt="Porträt von {contact.name}" title="{contact.name -> f:format.stripTags()}" maxWidth="100" />
must be
<f:image image="{contact.photo}" alt="Porträt von {contact.name}" title="{contact.name -> f:format.stripTags()}" maxWidth="100" />
<f:image image="{contact.photo.uid}" alt="Porträt von {contact.name}" title="{contact.name -> f:format.stripTags()}" maxWidth="100" />
must be
<f:image image="{contact.photo}" alt="Porträt von {contact.name}" title="{contact.name -> f:format.stripTags()}" maxWidth="100" />