WordPress automatically adds a wlwmanifest link to your site header for Windows Live Writer support. This is a link tag with a reference to your site’s wlwmanifest.xml file:
<link rel="wlwmanifest" type="application/wlwmanifest+xml" href="https://wpassist.me/wp-includes/wlwmanifest.xml" />
However, this manifest is not used by most users out there. If you want to remove the wlwmanifest link from your site header, add the following code snippet to your functions.php file.
This code will simply unhook this function from the site header.
If you are a performance addict like me, then you would be interested in our free plugin to remove unnecessary code from your site header. Visit WPA UnPress page to get more information about it.