Change "reset password" mail and make it HTML

Like in the topic, I found some info on that already:
https://s14.codeinspot.com/q/2472332 – works nice
but does not parse the mail in html.

Tried to add filter into my functions.php
add_filter( ‘wp_mail_content_type’, ‘set_html_content_type’ );
but then, instead of getting nice html email, I got html code as a downloadable .txt file in the email.

Please guide me someone how to make it work ?? I can edit wp-login if needed (I have it edited to make it frontend, at all)

thanks