I have installed Custom Scrollbars by Wesley Branton which gives me wide vertical scrollbars with up/down arrows in Outlook email. This has started disappearing and reverting to default narrow bars without arrows, maybe I am accidentally clicking somewhere in the reading pane? To get the wide bars back I have to delete the Add-on, close the computer, then re-install the Add-on. Can anyone advise what is going on here and how I can get the wider bars/arrows to stay permanently. thanks in advance Barry Wndows10 with Firefox