fixed an issue where toggling right palette would put the tools and area in an inconsistent state

src/desktop/UBDesktopAnnotationController.cpp

@@ -129,6 +129,7 @@ UBDesktopAnnotationController::UBDesktopAnnotationController(QObject *parent, UB
     connect(mDesktopPalette, SIGNAL(minimizeStart(eMinimizedLocation)), this, SLOT(onDesktopPaletteMinimize()));
     connect(mDesktopPalette, SIGNAL(mouseEntered()), mTransparentDrawingScene, SLOT(hideTool()));
     connect(mRightPalette, SIGNAL(mouseEntered()), mTransparentDrawingScene, SLOT(hideTool()));
+    connect(mRightPalette, SIGNAL(pageSelectionChangedRequired()), this, SLOT(updateBackground()));
 
     connect(mTransparentDrawingView, SIGNAL(resized(QResizeEvent*)), this, SLOT(onTransparentWidgetResized()));