As of WordPress 4.6 it is possible to hook into the wp_send_new_user_notifications action to disable the new user notifications send to site admins or the new user.

// The Parameter "$behaviour" can be set to:
// "none" (no notifications are send); 
// "default" (no changes); 
// "admin" (notifications send to admin only); 
// "user" (notification send to user only); 
// "both" (notifications send to admin + user)
public static function limitNewRegistrationNotifications($behaviour){
    // do nothing
    if ($behaviour == 'default'){
        return;
    }

    // handle user registrations (self registered users)
    remove_action('register_new_user', 'wp_send_new_user_notifications');

    // new users added via wp-admin are created using add_user() -> edit_user() chain, NOT register_new_user()
    // @see https://developer.wordpress.org/reference/functions/add_user/
    remove_action('edit_user_created_user', 'wp_send_new_user_notifications', 10, 2);

    // notifications disabled ?
    if ($behaviour == 'none'){
        return;
    }

    // add custom callback and override the $notify setting with custom behaviour
    add_action('register_new_user', function($user_id) use ($behaviour){
        // trigger notification
        wp_new_user_notification($user_id, null, $behaviour);
    });
    add_action('edit_user_created_user', function($user_id) use ($behaviour){
        // trigger notification
        wp_new_user_notification($user_id, null, $behaviour);
    });
}

This Tweak is available as part of the Tweakr WordPress Plugin.

Sometimes it is necessary to retrieve the current Document Title (used in the title tag) without the blog name or separators. As of WordPress 4.4 the wp_get_document_title() function become available which should be used to fetch the title – unfortunately it doesn’t accept any arguments and it is not possible to access the pure page title directly. Instead we can hook into the document_title_parts filter which allows us to access all title parts (title, page, tagline, site).

Workaround#

// workaround to retrieve the document title
function getDocumentTitle(){
    // temporary title
    $documentTitle = 'Unknown';

    // extractor function
    $extractor = function($parts) use (&$documentTitle){
        if (isset($parts['title'])){
            $documentTitle = $parts['title'];
        }
        return $parts;
    };

    // add filter to retrieve the page title
    add_filter('document_title_parts', $extractor);

    // trigger title generation
    wp_get_document_title();

    // remove filter
    remove_filter('document_title_parts', $extractor);

    // return result
    return $documentTitle;
}

Every WordPress Power User knows the awesome Contact Form 7 plugin. It is (one of) the best plugins to create custom forms without any PHP knowledge – especially useful for endusers/customers.

But sometimes you need to create select list values programmatically. Unfortunately the Contact Form 7 Docs are very poor in matter of advanced use cases including the build-in filter hooks.

WPCF7 Form Editor#

Just add a unique name to the data attribute – in this example my.data.provider. This allows you to match the element within the filter hook!

<p>
<label> My List
    [select mylist include_blank data:my.data.provider]
</label>
</p>

Filter Hook#

Roll the drums…the magical filter hook wpcf7_form_tag_data_option allows you to alter the options list and add options/values to the select list within a simple callback

add_filter('wpcf7_form_tag_data_option', function($n, $options, $args){
    // special data provider tag found ?
    if (in_array('my.data.provider', $options)){
        return get_my_value_list();
    }

    // default - do not apply any changes within the options
    return null;
}, 10, 3);

Well, thats it!

You may have noticed, that normal users (especially Author’s and Contributor’s) are not allowed to use all kind of HTML Tags and related Attributes.

Those elements got removed by the WordPress buil-in KSES Filter – and it’s a very useful feature in matter of security to prevent html-code-injection.

But sometimes it is required to enable some additional html tags and/or attributes. You can modify the list of allowed html tags and attributes by appling a custom filter:

The Filter#

Example how to allow EnlighterJS related attributes for pre and code tags

function ksesAllowHtmlCodeAttributes($data, $context){
    // only apply filter on post-context
    if ($context === 'post'){

        // list of all available enlighterjs attributes
        $allowedAttributes = array(
            'data-enlighter-language' => true,
            'data-enlighter-theme' => true,
            'data-enlighter-group' => true,
            'data-enlighter-title' => true,
            'data-enlighter-linenumbers' => true,
            'data-enlighter-highlight' => true,
            'data-enlighter-lineoffset' => true
        );

        // apply to pre and code tags
        $data['pre'] = array_merge($data['pre'], $allowedAttributes);
        $data['code'] = array_merge($data['code'], $allowedAttributes);
    }

    return $data;
}

// add the filter function (2 arguments and priority 100)
add_filter('wp_kses_allowed_html', 'ksesAllowHtmlCodeAttributes', 100, 2);

Sometime you want to add special links directly to the plugin-page. For example, you can enable an easy access to the plugin’s settings-page or to related docs/resources. All the magic is done within the plugin_row_meta hook.

It’s important to check which plugin is currently processed (there are no plugin/namespace specific hooks). Therefore you have to check which plugin-(main)file is selected: if ($file == 'enlighter/Enlighter.php'){

Additional links can be added to the $links array including I18n support.

Appearance#

How it’s done#

// add links
add_filter('plugin_row_meta', 'addPluginPageLinks', 10, 2);

// links on the plugin page
function addPluginPageLinks($links, $file){
  // current plugin ?
  if ($file == 'enlighter/Enlighter.php'){
    $links[] = '<a href="'.admin_url('options-general.php?page='.plugin_basename(__FILE__)).'">'.__('Settings', 'enlighter').'</a>';
    $links[] = '<a href="https://twitter.com/andidittrich">'.__('News & Updates', 'enlighter').'</a>';
  }
  
  return $links;
}