(re)moving the right block thingy

[Rolenet]

Though if you're using 1024 there might not be much I can do to help.

I understand, however I tried on these different computers on 1280 screens:
Win7 FF49
Win7 FF28
Win7 IE9.0.8
Win10 FF49
Win10 Edge
MacOS FF

Then I tried FF49 on different res, from 1024 to 1920.

I never even saw the slider arrow.