Simplification

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

@@ -222,12 +222,10 @@ public class MessageHelper {
             String email = ((InternetAddress) message.from[0]).getAddress();
             String name = ((InternetAddress) message.from[0]).getPersonal();
             if (identity != null && identity.sender_extra &&
-                    identity.email.contains("@") &&
-                    email != null &&
-                    email.contains("@") &&
-                    message.extra != null &&
-                    !message.extra.equals(identity.email.split("@")[0])) {
+                    email != null && message.extra != null) {
                 int at = email.indexOf('@');
+                String username = identity.email.split("@")[0];
+                if (at > 0 && !message.extra.equals(username)) {
                     if (message.extra.length() > 1 && message.extra.startsWith("+"))
                         email = email.substring(0, at) + message.extra + email.substring(at);
                     else
@@ -236,6 +234,7 @@ public class MessageHelper {
                         name = null;
                     Log.i("extra=" + email);
                 }
+            }
             imessage.setFrom(new InternetAddress(email, name, StandardCharsets.UTF_8.name()));
         }