--- fmt.html	2017-08-08 12:35:19.648087900 +0200
+++ fmt.html	2017-08-11 13:26:31.110788600 +0200
@@ -76,6 +76,7 @@
     set hdr ""
 
     if {![Get raw]} {
+	append  hdr [markup {<!DOCTYPE html>}]
 	append  hdr [tag html] [tag head] \n
 	append  hdr [tag_ title $pagetitle] \n
 
