TYPO3 Core

We set up a small flexform for selecting a database record:

<settings.flexform.news>
<TCEforms>
<label>Topic</label>
<config>
<type>group</type>
<internal_type>db</internal_type>
<allowed>tx_mynews_domain_model_news</allowed>
<minitems>1</minitems>
<maxitems>1</maxitems>
<multiple>0</multiple>
<size>1</size>
<wizards>
<suggest>
<type>suggest</type>
</suggest>
</wizards>
</config>
</TCEforms>
</settings.flexform.news>

As soon as minitems is set to 1, the field will be rendered as invalid. Even selecting a record does not remove the red sign. An editor is unable to save the flexform