Allow matching domain names

FAQ.md

@@ -1440,6 +1440,7 @@ It is possible to configure a [regex](https://en.wikipedia.org/wiki/Regular_expr
 to match **the username** of an email address (the part before the @ sign).
 
 Note that the domain name (the parts after the @ sign) always needs to be equal to the domain name of the identity.
+Since version 1.1640 it is possible to match the full email address with a regex, which can be useful for matching alias domain names.
 
 If you like to match a catch-all email address, this regex is mostly okay:
 

app/src/main/java/eu/faircode/email/EntityIdentity.java

@@ -157,12 +157,12 @@ public class EntityIdentity {
         if (cother.length != 2 || cemail.length != 2)
             return false;
 
-        // Domain
-        if (!cother[1].equalsIgnoreCase(cemail[1]))
-            return false;
-
-        // User
         if (TextUtils.isEmpty(sender_extra_regex)) {
+            // Domain
+            if (!cother[1].equalsIgnoreCase(cemail[1]))
+                return false;
+
+            // User
             int plus = cother[0].indexOf('+');
             String user = (plus < 0 ? cother[0] : cother[0].substring(0, plus));
             if (user.equalsIgnoreCase(cemail[0]))