TF-1706 Fix grey bar on server CYRUS

(cherry picked from commit 3ae632c967607cd84ddd79da8d9e17421f6b31ff)

model/lib/email/presentation_email.dart

@@ -73,6 +73,22 @@ class PresentationEmail with EquatableMixin {
     }
   }
 
+  String get firstEmailAddressInFrom {
+    if (from?.isNotEmpty == true) {
+      return from!.first.emailAddress;
+    } else {
+      return '';
+    }
+  }
+
+  EmailAddress? get firstFromAddress {
+    if (from?.isNotEmpty == true) {
+      return from!.first;
+    } else {
+      return null;
+    }
+  }
+
   String getAvatarText() {
     if (getSenderName().isNotEmpty) {
       return getSenderName().firstLetterToUpperCase;

model/lib/extensions/presentation_email_extension.dart

@@ -19,7 +19,11 @@ import 'package:model/mailbox/select_mode.dart';
 extension PresentationEmailExtension on PresentationEmail {
 
   List<Color> get avatarColors {
-    return from?.first.avatarColors ?? AppColor.mapGradientColor.first;
+    if (from?.isNotEmpty == true) {
+      return from!.first.avatarColors;
+    } else {
+      return AppColor.mapGradientColor.first;
+    }
   }
 
   int numberOfAllEmailAddress() => to.numberEmailAddress() + cc.numberEmailAddress() + bcc.numberEmailAddress();