Denis Yanchevskiy

Allows you to make post, page, custom post elements required: title, content, featured image.
After installing the plugin, you need to go to the Settings -> DCO Post Validator to specify the required elements.

DCO Post Validator

Allows you to make post, page, custom post elements required: title, content, featured image.

mitcho (Michael Yoshitaka Erlewine)

This infrastructure plugin adds basic UI for single-valued taxonomies, i.e. a taxonomy with presents a <code>select</code> widget.
<h4>Usage</h4>
When registering your custom taxonomy, add the argument <code>single_value</code> set to <code>true</code> to get the single value UI. If a selection of this term is required, also add <code>required</code> set to <code>true</code>.
<pre><code>register_taxonomy(
 'astrological_sign',
 array( 'person' ),
 array(
 'hierarchical' => false,
 'show_ui' => true,
 'required' => true,
 'single_value' => true
 )
);
</code></pre>
Development of this plugin supported by <a href="http://globalshakespeares.org" rel="nofollow ugc">MIT Global Shakespeares</a>.

Single Value Taxonomy UI

This infrastructure plugin adds basic UI for single-valued taxonomies, i.e. a taxonomy with presents a select widget.

DCO Post Validator vs Single Value Taxonomy UI