problem disabling plugin only for mobile

I am trying to enable a plugin only for mobile and I have consulted this thread: Deactivate plugins only for mobile devices

I have made some changes to the last function as I want to enable only for mobile, while the thread suggest how to disable to mobile.

I don’t know how specify the plugin that I want to specify, so I include 2 files. This is in a folder in my wp-content/ plugins/name-of-plugin, where there are an index.php file and a name-of-plugin.php file.

This is my code, saved in a my-code.php file, places on mu-plugins of wordpress. Unfrotunately, it doesn’t work. Any help how to fix this?

 <?php  /**  * Plugin Name: My mobile enabler  */  function my_non_mobile_plugins() {   return array(      // i am not sure how specifiy the plugin I want to disable. I have added these two lines      '/name-of-folder-plugin/plugin-name.php',     '/name-of-folder-plugin/index.php'   ); }  function my_is_mobile() {    $  is_mobile = false;   if ( strpos($  _SERVER['HTTP_USER_AGENT'], 'Mobile') !== false     || strpos($  _SERVER['HTTP_USER_AGENT'], 'Android') !== false     || strpos($  _SERVER['HTTP_USER_AGENT'], 'Silk/') !== false     || strpos($  _SERVER['HTTP_USER_AGENT'], 'Kindle') !== false     || strpos($  _SERVER['HTTP_USER_AGENT'], 'BlackBerry') !== false     || strpos($  _SERVER['HTTP_USER_AGENT'], 'Opera Mini') !== false     || strpos($  _SERVER['HTTP_USER_AGENT'], 'Opera Mobi') !== false   ) {     $  is_mobile = true;   }   return $  is_mobile; }   add_filter( 'option_active_plugins', 'my_disable_plugins_for_mobiles' );  function my_disable_plugins_for_mobiles( $  plugins ) {    if ( ! my_is_mobile() ) {   $  not_allowed = my_non_mobile_plugins(); // get non allowed plugins    return array_values( array_diff( $  plugins, $  not_allowed ) );        }  return $  plugins; // for mobile device do nothing  }