Comfortable Changes is a QoL that tries to give the player more control, through dedicated keys, of the different mechanics game, such as flying (creative and elytras) and actions such as jumping (with jump buff) and the use of the left hand in a dedicated way.
What the mod currently adds:
It allows you to activate the Elytras with V (Default) from the ground, it also allows you to deactivate flight in the air.
Allows you to activate Creative Flight (if the character is allowed it) with X (Default) from the ground.
A dedicated key to use the off-hand object directly, regardless of what you have in your main hand, in addition, a modifier key that, when held and right-clicked, prioritizes the off-hand.
All these controls are configurable, and from the configuration you can activate or deactivate the vanilla way in which the flight with elytras and the creative are activated.
It also allows more control when jumping when under the effect of Jump Boost. Now, to reach the maximum height that the effect allows, you must hold down the run key, otherwise the jump will be as if there were no effect, that is, one and a half blocks. There is no config for this but I'm going to add it