Unable to map MWheelUp=+lookup

[Phoebe Crennersit]

Hello and thanks for the help,
I'd like to use the mouse-wheel to look-up and look-down.

In lzdoom.ini under "[Doom.Bindings]", I've tried changing to:
MWheelUp=+lookup
MWheelDown=+lookdown
It failed

Within the game, I've also tried customizing the "look up" and "look down" actions to map to the mouse wheel.
Unfortunately, it also failed.

I can successfully map "+lookup" and "+lookdown" to keys, but not to "MWheelUp" and "MWheelDown".
So I assume that I'm doing something wrong.

I'd appreciate guidance.
Thank you.

[drfrag]

You can't do that in old GZDoom versions, must be an old bug.

[Graf Zahl]

You cannot bind the mouse wheel to 'button' actions (i.e. the ones starting with '+'.)
These require a key to be held down, but the mouse wheel cannot be held down so these buttons never register as 'pressed'.