Just FYI really: the list of open challenges now “locks in place” when you move your mouse over it, so that you don’t end up clicking on the wrong challenge because some other one disappeared from the list just as you went to click.
If the actual challenge you are trying to accept gets accepted by someone else while you are moving your mouse, its button changes to “cant accept”. When you stop moving your mouse, the list will update again.
GaJ
What if the offer is displaced by another offer that just appeared? (I think I just saw that happen.)
Could be remedied by sorting oldest>newest offers top>bottom.
That is what this fixes.
All offers will stay in place (and no others will appear) while you are actually moving your mouse.
If they are taken by someone else while your mouse is moving, the button is replaced by “cant accept” (the offer itself remaining in place in the list while your mouse is moving towards it).
(no amount of sorting can help without this sort of fix, becuase an offer can always disappear from above where you are about to click, hence this fix 
)
Ah, maybe I have to relog for this to take effect?
Oh and I was referring to some offer being pushed down because a new one appeared. That would be solved by sorting old>new. The lock thing only solves dis-appearing offers if I understood this correctly.
It might need a browser reload to take effect.
It’s’s subtle, because it’s only locked while you are moving (and a short period after you stop).
This is so that once you start moving towards your choice, it doesn’t disappear from underneath you, but otherwise you get updates as fast as practically possible.
Yes, if we sorted old->new at the bottom, then newly appearing ones aren’t a problem. Actually, I suspect that’s how it was before. The lock solves the problem of older ones disappearing and everything “popping up” one or more entries.
Since they appear and disappear at the same rate (average over time) then you would have a problem whichever way you sort
You can prove to yourself that it is working by just gently continually twitching your mouse over the list. You should see the offers gradually having their buttons replaced by “cant accept”. When you stop moving your mouse (a second after) the list will update with the latest.