I have already posted this on PureZC, but just to be sure I repost it here. :)

No idea if this was fixed or not, I'm using 2.50.2 still.

It's possible to use the hookshot through a 1 tile tall solid wall upwards if you stand exactly 4 pixels (i believe) away from the wall.

Don't even know if this has always been the case.
It only seems to happen with diagonal walking enabled.

Edit: I used a wrong bug icon tag. oops