Default disable TCP keep alive

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

@@ -90,7 +90,7 @@ public class ApplicationEx extends Application implements SharedPreferences.OnSh
         final boolean crash_reports = prefs.getBoolean("crash_reports", false);
 
         try {
-            boolean tcp_keep_alive = prefs.getBoolean("tcp_keep_alive", true);
+            boolean tcp_keep_alive = prefs.getBoolean("tcp_keep_alive", false);
             System.setProperty("fairemail.tcp_keep_alive", Boolean.toString(tcp_keep_alive));
         } catch (Throwable ex) {
             Log.e(ex);

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

@@ -295,7 +295,7 @@ public class FragmentOptionsConnection extends FragmentBase implements SharedPre
         etTimeout.setHint(Integer.toString(EmailService.DEFAULT_CONNECT_TIMEOUT));
 
         swPreferIp4.setChecked(prefs.getBoolean("prefer_ip4", true));
-        swTcpKeepAlive.setChecked(prefs.getBoolean("tcp_keep_alive", true));
+        swTcpKeepAlive.setChecked(prefs.getBoolean("tcp_keep_alive", false));
         swSslHarden.setChecked(prefs.getBoolean("ssl_harden", false));
     }
 

app/src/main/res/layout/fragment_options_connection.xml

@@ -201,7 +201,6 @@
             android:layout_width="0dp"
             android:layout_height="wrap_content"
             android:layout_marginTop="12dp"
-            android:checked="true"
             android:text="@string/title_advanced_tcp_keep_alive"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent"