This how-to guides developers through the steps necessary to disable default TinyMCE handling of the <embed> and <object> tags.

Proceeding with this guide will disable the ability of the CMS to embed .swf files through the "Insert Media" interface button. You will need to provide your own custom TinyMCE plugins or embed the files directly via HTML code.

Disable the media plugin

CMS uses the TinyMCE media plugin to embed .swf files. The side effect of this is that <embed> and <object> tags are managed by the plugin which sometimes prevents custom markup to be inserted, or rewrites it with custom names and attributes.

In your module's _config.php (the module's name has to be alphabetically after cwp for your _config.php statements not to be overriden, see the notice in the Rich Text Editing docs) disable the media plugin for the default editor installed by the cwp module:

use SilverStripe\Forms\HTMLEditor\HTMLEditorConfig;


Note the editor configuration we want to amend is "cwp" here, different from the default SilverStripe configuration called "cms".

You should now be able to embed any <embed> or <object> using the HTML button in the TinyMCE editor.

Modifying the whitelist

If you find out some attributes are still being removed by the editor, your can update the whitelist of elements. Copy the extended_valid_elements option from cwp/_config.php, and amend it in your own _config.php to suit.

use SilverStripe\Forms\HTMLEditor\HTMLEditorConfig;

HTMLEditorConfig::get('cwp')->setOption('extended_valid_elements', '<your modified whitelist goes here>');```

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