grammar: Allow underscore in domain names

MB · MB · commit 54c5c953560a · 2016-05-20T23:41:57.000Z
Not valid, but browsers handle it.

Fixes: 527bfee5392da4a58d44d572d9785610e79fcf0a
diff --git a/utils/relaxng.xml b/utils/relaxng.xml
@@ -33,7 +33,7 @@
       <element name="target">
         <attribute name="host">
           <data type="string">
-            <param name="pattern">(([A-Za-z0-9äö-]+|\*)\.)*([A-Za-z0-9äö-]+|\*)</param>
+            <param name="pattern">(([A-Za-z0-9äö_-]+|\*)\.)*([A-Za-z0-9äö-]+|\*)</param>
           </data>
         </attribute>
       </element>
