在Wordpress上更改x-iframe选项

Question

When I embed wordpress into iframe, then login and other pages not work. I see that is caused by x-iframe-opions of WP set to deny embed of iframe for security reason.

I found this solution but not work with last WP:

remove_action( 'admin_init', 'send_frame_options_header', 10, 0 );
remove_action( 'login_init', 'send_frame_options_header', 10, 0 );

I try also via htaccess but not work:

 <IfModule mod_headers.c>
   Header set X-Frame-Options allow
   Header always append X-Frame-Options "ALLOW-FROM http://domain.com"
 </IfModule>

I see that allow-from work only for certain browser, however I would like to allow if possible only for a certain domain, or from all domains.