Spontaneously couldn't use righ click. Right click to block with knife works, but not with climbing picks. Couldn't climb with normal jump either. Tried to remap the button .. didn't work. Had to travel to respit for it to work again equally 'spontaneously'.
this also breaks regular climbing (space)
same in multiplayer
Same here, the right-click grapple for the climbing picks stop working seemingly at random. I'm currently seeing this in Offline mode when playing with friends in co-op most predominantly; relogging fixes it though!