Completely reworked mouse handling - should now be smoother due to there no longer being a multi-layered game of telephone going on with all the various interim coordinate counters, also rewritten the serial mouse emulation ground ground up.

src/qt/qt_main.cpp

@@ -256,7 +256,6 @@ main(int argc, char *argv[])
     auto rawInputFilter = WindowsRawInputFilter::Register(main_window);
     if (rawInputFilter) {
         app.installNativeEventFilter(rawInputFilter.get());
-        QObject::connect(main_window, &MainWindow::pollMouse, (WindowsRawInputFilter *) rawInputFilter.get(), &WindowsRawInputFilter::mousePoll, Qt::DirectConnection);
         main_window->setSendKeyboardInput(false);
     }
 #endif