Just finish

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

@@ -70,10 +70,8 @@ abstract class ActivityBase extends AppCompatActivity implements SharedPreferenc
     public void onSharedPreferenceChanged(SharedPreferences prefs, String key) {
         Log.i(Helper.TAG, "Preference " + key + "=" + prefs.getAll().get(key));
         if ("theme".equals(key) ||
-                (!this.getClass().equals(ActivitySetup.class) && ("compact".equals(key) || "debug".equals(key)))) {
+                (!this.getClass().equals(ActivitySetup.class) && ("compact".equals(key) || "debug".equals(key))))
             finish();
-            startActivity(getIntent());
-        }
     }
 
     private List<IBackPressedListener> backPressedListeners = new ArrayList<>();