P̶l̶a̶c̶e̶h̶o̶l̶d̶e̶r̶ *Default* content in Custom Post Type TinyMCE editor

Question

I know you can customize the placeholder default text of the 'Post Title' field, but is there any way to display placeholder content in the actual TinyMCE post editor? Ideally I'd like to display several paragraphs of HTML formatted content in the editor as a placeholder / instructions.

Answer 1

There is no way to add "placeholder" for TinyMCE, but you can set default content for newly created posts. All you need is just to hook default_content filter and return your formatted paragraphs:

add_filter( 'default_content', 'wpse8170_get_default_instructions', 10, 2 );
function wpse8170_get_default_instructions( $content, WP_Post $post ) {
    if ( $post->post_type == 'post' ) {
        $content = '.... your content ....';
    }
    return $content;
}

Answer 2

Here's a TinyMCE plugin I adapted to work with WordPress, does exactly what you need without actually setting it as the content:

https://github.com/tripflex/wp-tinymce-placeholder