Update Matrix ID

src/index.xhtml

@@ -47,7 +47,7 @@
                 <h2>Contact</h2>
                 <ul>
                     <li><b>Mail:</b> <a href="res/mail.png">Link to graphic with address</a> (<a href="res/nicolaslenz.pgp">PGP-Key</a>)</li>
-                    <li><b>Matrix messenger:</b> @Eisfunke:matrix.org</li>
+                    <li><b>Matrix messenger:</b> @eisfunke:eisfunke.com</li>
                     <li><b>Telegram messenger:</b> @Eisfunke</li>
                     <li><b>Signal messenger:</b> Available</li>
                     <li><b>Briar messenger:</b> Available</li>