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<?php
/**
* Plugin Name: Envira - Remove Add Gallery Button
* Plugin URI: http://enviragallery.com
* Version: 1.0
* Author: Erica Franz
* Author URI: https://fatpony.me
* Description: Removes the Add Gallery button from all Visual Editors in WordPress
*/

add_filter( 'envira_gallery_media_button', 'remove_envira_gallery_media_button' );
function remove_envira_gallery_media_button( $button ) {
    return '';
}