Add button to TinyMCE in comments

Hello and good day,

I had added the rich text code editor to my comments using this snippet:
https://sumtips.com/how-to/add-rich-text-editor-wordpress-comment-form-without-plugin/

However, it seems in the code there is an area to add advanced buttons. Which would I need to get yours to work?

'tinymce' => array(
        	'theme_advanced_buttons1' => 'bold,italic,underline,strikethrough,bullist,numlist,code,blockquote,link,unlink,outdent,indent,|,undo,redo,fullscreen',
	        'theme_advanced_buttons2' => '', // 2nd row, if needed
        	'theme_advanced_buttons3' => '', // 3rd row, if needed
        	'theme_advanced_buttons4' => '' // 4th row, if needed
  	  	),