wlwmanifest.xml is a static file with information on how Windows Live Writer can talk to WordPress. It has nothing to do with security or performance. This file doesn’t reveal your website information.
If you just love to keep your head area net and clean then you can remove it. If you have opened your page source, you will something like the following code. This is the WLW Manifest.
Removing wlwmanifest from the head is super easy. Login to your Cpanel or FTP and navigate to the active theme’s root directory. Search for the function.php file and open it via editor.
Paste the following code and save your function.php file.
// REMOVE wlwmanifest.xml. remove_action('wp_head', 'wlwmanifest_link');
Let’s check another method where you don’t need to work with code. Just install WP Adminify plugin. Navigate to WP Adminify > Tweaks > Head > Remove WLW Manifest Link. Now enable this option and save your plugin settings.