Jagg wrote: Wed Jan 10, 2018 1:37 am Ok, so this is a chart display bug on your mt4, isn't it? (never saw such a line on my mt4)

NO bug in my mt4 terminal
Seems you are not trying search find chart property options for to learn,if you want see your chart like mine,copy options from upper picture
and try playing option alike in lower picture -
at arrow 1 inside blue circle you see a little arrow pointing down,drag it right left with holding mouse left click
at arrow 2,any where inside this pan,hold mouse left click and drag up down for to decrease/increase chart/candles length vertically - this will increase/decrease scroll bar length too (the white one you was talking about)
at arrow 3 drag this scroll bar up/down to move your chart up/down
hope it help you