First things first. Amazing job, you should really be proud of yourself with what you've done here.
That aside, the mod suffer from some lack of basic QoL.

Firstly, allow gliders to be assigned in 'Trinkets' Cape Slot'.
Simple and effective change, I'd understand if it wasn't done like this to follow basic elytra balance rules, but Curios allows gliders to be placed in their own unique slot, so... yeah.

Secondly, allow us to change the key bind to activate gliding.
You might be asking yourself why, well simply put, it glides at the wrong times automatically.
Say you're jumping over a ledge to the block in front of you in a 45 degree angle, the glider will activate.
This is very much annoying and can be fixed easily with the suggested change.

Thirdly, fix the compatibility issue with FastAnim and First Person Model.
Now I will admit, this is not exactly a simple thing, and the latter part of the suggestion might need to be done by the mod's author, however FastAnim should be an easy fix, and while not exactly a must have mod, it does improve performance by a good bit, so why sacrifice on that?

Fourthly, you seem to have messed up the durability of the gliders.
The basic one is 500 durability, and the iron one is 50.
Furthermore, I'm not sure if this is your doing or just the way the game handles durability changes, but using the glider for very short 'bursts' of times allows it to be abused without suffering said durability changes.

Hope you read this soon, cheers.
(Also these issues are on 1,19,2, but I'd expect them to be on just about every version.)

There seems to be a bug where the glider just does not 'de-activate', could possibly be solved by the different keybind thing?

On a side note, a configurable speed and trinket slot would be lovely.

Thank you for labeling it, I'm new to GitHub so I wasn't sure how to do it myself.