Thats correct. Its the tickbox that is really hard to check in FireFox 60 on android. You really need to zoom in and then tick it. You cannot just click on the line like with normal tickboxes. You really have to hit the exact space inside the tiny square. And some PE styles do not seem to display the border of the tiny square.
I do know that FireFox has changed some things in FF 60 that makes links in some sliders unclickable. Im not sure if this is related or not.