Operating System: Windows 10.
Browser: Firefox 63.0.3.
Extensions: None (have disabled uBlock on GB).
The carousels don't have forward/back buttons in Firefox, I've checked in Chrome and they appear there fine.
I did a bit of investigation and it looks like there's a .touchevents class on the body tag that's causing these buttons to be hidden via this style:
I guess the site is detecting that I should be using touch events? I'm on a PC with no touch devices (that I know of) though so not sure why.