Hi Marco, currently the scroll bar appearance comes from the Qt "fusion" style:

You can modify it though to suit you better. To do that you'll need to edit moi.css which is in the ui sub-folder in the program install.

Add this to the bottom of moi.css :

::-webkit-scrollbar {
    width: 10pt;
    height: 10pt;
}

::-webkit-scrollbar-track {
	background:rgb(230, 230, 230);
	border:1px solid rgb(200,200,200);
}

::-webkit-scrollbar-thumb {
	border-radius:5pt;
	background:rgb(170,170,170);
	border: 1px solid rgb(150,150,150);
}

::-webkit-scrollbar-thumb:hover {
	background:rgb(180,180,180);
}

- Michael