There's only one 1 way to fix this.
The Formatting options need to be in their contextual tabs in the Ribbon where there's a lot more room.
See my post here... which includes link to the Idea already created
Thanks for this. I have also just spent ages looking and I too missed the grey scrollbar inside the second grey scrollbar inside the sligtly darker grey background. It is a bit too subtle!
I was just trying to fix the fact that on a grouped bar and line graph it had set the scales differently for the line and bar values. I would have though it better to default to the same scale for both (i.e. 0% - 100%) as I would have thougt that would normally be the desired outcome.