Added Surface Duo 2 support

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

@@ -280,7 +280,8 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
                     content_frame.setLayoutParams(lparam);
                 }
                 // https://docs.microsoft.com/en-us/dual-screen/android/duo-dimensions
-                content_separator.getLayoutParams().width = Helper.dp2pixels(this, 34);
+                int seam = (Helper.isSurfaceDuo2() ? 26 : 34);
+                content_separator.getLayoutParams().width = Helper.dp2pixels(this, seam);
             } else {
                 int column_width = prefs.getInt("column_width", 67);
                 ViewGroup.LayoutParams lparam = content_pane.getLayoutParams();

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

@@ -1472,7 +1472,19 @@ public class Helper {
     }
 
     static boolean isSurfaceDuo() {
-        return ("Microsoft".equalsIgnoreCase(Build.MANUFACTURER) && "Surface Duo".equals(Build.MODEL));
+        return (isSurfaceDuo2() ||
+                ("Microsoft".equalsIgnoreCase(Build.MANUFACTURER) && "Surface Duo".equals(Build.MODEL)));
+    }
+
+    static boolean isSurfaceDuo2() {
+        /*
+            Brand: surface
+            Manufacturer: Microsoft
+            Model: Surface Duo 2
+            Product: duo2
+            Device: duo2
+         */
+        return ("Microsoft".equalsIgnoreCase(Build.MANUFACTURER) && "Surface Duo 2".equals(Build.MODEL));
     }
 
     static boolean isArc() {