Definitely not working with WP 5.8.1 is there an alternative?

I’m not using this plugin – but basically one of my plugins uses a similar code to remove RSS feeds.

What exactly happens, if you enable this plugin? – You get a blank page, when visiting the website?

After some investigation I realized, that

remove_action('wp_head', 'feed_links', 2);

seems to trigger the problem. A similar code like

\add_filter( 'feed_links_show_posts_feed', function($show) {
  return false;
}, 9999, 1 );
\add_filter( 'feed_links_show_comments_feed', function($show) {
  return false;
}, 9999, 1 );

did not fix this.

There are no breaking changes in the WordPress API here. Therefore it looks to me like a bug in WordPress – not within this plugin.

By the way

remove_action('wp_head', 'feed_links', 2);

is basically suggested anywhere to remove feed links from HTML header. If any other plugin would provide those features, I doubt, that they would use a different mechanism.

I guess, removing RSS feeds with this approach is currently just broken.

Sorry for spamming in this thread.

After some more investigations I found out, that the Divi Theme used on my customers website was the root for the problem. I don’t know, if you also use it.

After disabling the option Enqueue jQuery Compatibility Script in Divi theme settings, the problem was gone.

Maybe you also have those side effects with the installed theme or with other installed plugins. Try to disable all plugins and enable them one by one. Also you might try to test, if the problem occurs with another theme, too.