Since google/ youtube pulled object/embed support for embedded youtube videos, here is a wordpress filter for attempting to replace object embeds with video specifiers for use in other plugins (code could be adjusted for direct iframes too), it checks to see if an iframe or youtube reference already exists as it builds up an array of youtube urls – only uses first youtube url found. It assumes any youtube urls are in . Maybe of use to somebody.

function replaceyoutubeobject($string) {
    if(stripos($string,'iframe')===false) {
    if(stripos($string,'+<\/object>/smi", "", $string); // remove old objects
    $match = $matches[0];
    $url = $match[0];
    if(stripos($url,"/v/")!==false) {
    $u=explode("/v/",$url);
    } else if(stripos($url,"v=")!==false) {
    $u=explode("v=",$url);
    }
    $u1=$u[0];
    $u2=$u[1];
    $ext=explode("&",$u2);
    $vcode=$ext[0];
    $string = "
\n".$string;
    }}}
    return $string;
}
add_filter( 'the_content', 'replaceyoutubeobject' );

If you log into admin dashboard via wordpress and are faced with blank/white dashboard areas, try the following fix.

Open file blog/wp-admin/includes/screen.php in your favorite text editor.
On line 706 or close by (depending on version) find the following PHP statement: echo self::$this->_help_sidebar;
Replace it with the statement: echo $this->_help_sidebar;
Save your changes.
Go to a dashboard page.

If you have parked domains on a single wordpress website, referenced under the root of the domain, but want the site urls displayed to be based on parked domain used. Consider adding the following code to the wp-config.php file.

define('WP_SITEURL', 'http://'.$_SERVER['HTTP_HOST']);
define('WP_HOME',    'http://'.$_SERVER['HTTP_HOST']); 

Sometimes yahoo blocks server smtp email checks, so emails aren’t sent out to none yahoo addresses. This can be solved using the code below (tested for wordpress 3.9, and latest version of contact form 7 plugin):

if (!function_exists('cf7_redirect_yahoo')) {

function cf7_redirect_yahoo($cf7)
{

       $domain = get_option("siteurl");
       $domain = str_ireplace("http://","",$domain);
       $domain = str_ireplace("www.","",$domain);
       $fd=explode("/",$domain);
       $nmail="noreply@".reset($fd);
       $mail = $cf7->prop('mail');

       $submission = WPCF7_Submission::get_instance();
       if($submission) {
       $posted_data = $submission->get_posted_data();
       foreach ($posted_data as $keyval => $posted) {
       if(stripos($keyval,'email')!==false) {
       if(stripos($posted,'yahoo')!==false) {
       $mail['sender'] = $nmail;
       $cf7->set_properties( array( 'mail' => $mail ) );
       }}}}

       return $cf7;
}
}

In wordpress Contact Form Plugin version 3.9 onwards the structure of the plugin changed, and this has had a major impact on the wpcf7_before_send_mail() hook usage. If you now want to access the email posted data – keys and post value, below shows the old method and then the new method. Hope it helps someone. Note that the posted_data object property no longer exists.

Old Method:

add_action("wpcf7_before_send_mail", "my_function");

function my_function(&$cf7)
{

foreach ($cf7->posted_data as $keyval => $posted) {
// use $keyval and $posted as elements in email forms
}

}

New Method:

add_action("wpcf7_before_send_mail", "my_function");

function my_function($cf7)
{
       $submission = WPCF7_Submission::get_instance();
       if($submission) {
       $posted_data = $submission->get_posted_data();
       foreach ($posted_data as $keyval => $posted) {
       // use $keyval and $posted as elements in email forms
       }
       }
}