The easy way (you need to repeat when you update to a newer version of WPMU) is to edit the file wp-includes/kses. php

Search for the line

add_filter('content_save_pre', 'wp_filter_post_kses');

and comment it out by placing two slashes in the beginning:

// add_filter('content_save_pre', 'wp_filter_post_kses');

That is all! Go embed your videos without problems – Or, you can follow a different, and more secure, way, by allowing just the video specific tags. Again in the file wp-includes/kses. php add the following tags in the allowed tags section:

'object' => array (
   'id' => array (),
   'classid' => array (),
   'data' => array (),
   'type' => array (),
   'width' => array (),
   'height' => array (),
   'allowfullscreen' => array ()),
'param' => array (
   'name' => array (),
   'value' => array ()),
'embed' => array (
   'id' => array (),
   'style' => array (),
   'src' => array (),
   'type' => array (),
   'height' => array (),
   'width' => array (),
   'quality' => array (),
   'name' => array (),
   'flashvars' => array (),
   'allowscriptaccess' => array (),
   'allowfullscreen' => array ()),

Or download the “Allow Embeded Videos” plugin for Wordpress MU and put it in the mu-plugins folder.

Tags: embed youtube videos, mu, WordPress MU, wp

Cf.

• Bulk delete tags from a Wordpress MU blog easily

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