PHP Htaccess html extension Hidden

.htaccess
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^\.]+)$ $1.php [NC,L]

index.php

<!DOCTYPE html>
<html>
<head>
<title>This index page.</title>
</head>
<body>
This is index page.
</body>
</html>

profile.php

<!DOCTYPE html>
<html>
<head>
<title>This index page.</title>
</head>
<body>
This is index page.
</body>
</html>

Demo 1