More OpenID improvements

public/.htaccess

@@ -28,7 +28,7 @@ RewriteRule .* https://%{SERVER_NAME}%{REQUEST_URI} [R=301,L]
 
 # rewrite OpenID clients to YADIS file
 RewriteCond %{HTTP_ACCEPT} ^application/xrds\+xml [NC]
-RewriteRule ^$ /yadis.xml [PT]
+RewriteRule ^$ /yadis.xrds [PT]
 
 # block files and folders beginning with a dot, such as .git
 # except for the .well-known folder, which is used for Let's Encrypt and security.txt
@@ -57,6 +57,7 @@ RewriteRule ^(.*) index.php [L]
 # MIME types
 <IfModule mod_mime.c>
 AddType application/pgp-keys asc
+AddType application/xrds+xml xrds
 </IfModule>
 
 # compress text file responses