Custom code snippet that allows you to allow and/or disallow filetyps for the File Uploader extension.

file-uploader-allow-filetypes.php

<?php 

// Add the following code snippet to the PHP section of the MainWP Custom Dashboard Extension

add_filter('mainwp_file_uploader_allowed_file_types', 'mycustom_mainwp_file_uploader_allowed_file_types');
function mycustom_mainwp_file_uploader_allowed_file_types( $types ) {
   $types[] = 'htaccess';
   return $types;
}

?>