Fix a DDE error on Windows (Bug #236)

ChangeLog

@@ -1,6 +1,8 @@
 # Version number followed by the release date
 
 1.3.1.0
+  * Fix a DDE error on Windows (Bug #236)
+  * gdk_x11_get_server_time crashes when an invalid window is passed
   * Migrate to PCRE2 (Miriam Ruiz)
 
 1.3.0.0 2020/08/15

src/myipc.cpp

@@ -140,8 +140,16 @@ IPCData *MyServerConnection::OnRequest
 {
 	if ( size == NULL )
 		return NULL;
+
+#if wxUSE_DDE_FOR_IPC
+	// wxDDEConnection::Request validates the return data
+	const static char data[] = "Data";
+	*size = 1;
+	return data;
+#else
 	*size = 0;
 	return NULL;
+#endif
 }
 
 bool MyServerConnection::OnStartAdvise ( const wxString& WXUNUSED ( topic ),