Two way foldable

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

@@ -184,7 +184,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
         content_separator = findViewById(R.id.content_separator);
         content_pane = findViewById(R.id.content_pane);
 
-        if (!portrait && !landscape3 && Helper.isSplitScreen()) {
+        if ((portrait ? portrait2 : !landscape3) && Helper.isFoldable()) {
             View content_frame = findViewById(R.id.content_frame);
             ViewGroup.LayoutParams lparam = content_frame.getLayoutParams();
             if (lparam instanceof LinearLayout.LayoutParams) {

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

@@ -677,7 +677,7 @@ public class Helper {
         return 0;
     }
 
-    static boolean isSplitScreen() {
+    static boolean isFoldable() {
         return ("Microsoft".equalsIgnoreCase(Build.MANUFACTURER) && "Surface Duo".equals(Build.MODEL));
     }