send fake lua key release event when going into another interface

src/gui/game/GameView.cpp

@@ -1622,6 +1622,8 @@ void GameView::OnBlur()
 	isMouseDown = false;
 	drawMode = DrawPoints;
 	c->MouseUp(0, 0, 0, 1); // tell lua that mouse is up (even if it really isn't)
+	if (GetModifiers())
+		c->KeyRelease(0, 0, false, false, false);
 }
 
 void GameView::OnTick(float dt)