There are some bugs about customize controls emerging in the new version 1.21.0, which can be annoying 

Scenario 1: Walking through scaffolding will set jump button to the size of 120%, and I set it to 200% beforehand.

Scenario 2: When setting customize controls in water, the up button can’t be selected. Instead, an unknown frame is selected.

Scenario 3: When setting customize controls on land and if you put jump button down enough, once getting in water, you’ll see the up and down buttons are almost stacked up.

Customize controls lets us put all these buttons wherever we want, but this is not free enough, we have been used to the old settings, meaning our muscle memory may not be able to do the things right if the places of buttons go against our muscle memory due to some bugs. Thus, I would like to give some suggestions, that is, letting us set jump button and the up and down buttons when in water or scaffolding separately, if everything goes well, I think it may solve the problems mentioned