The bug

When a dripleaf receives a redstone signal while only partially tilted, any entities on top if it such as the player will immediately clip through it.

Clipping through blocks is not desirable behaviour, with several cases of this being fixed before.

How to reproduce

1. Place a big dripleaf on the ground
2. Stand on the big dripleaf
3. While the dripleaf is only partially tilted (such that the hitbox is shorter and the player has fallen slightly), place a redstone torch next to the dripleaf to power it

Expected results

The player shouldn't clip through the dripleaf, as clipping through physically solid blocks has been historically considered undesirable behaviour. Refer to the "how to fix" section for three proposed solutions.

Actual results

The player just clips straight through the dripleaf.

How to fix

Any of the three following things should happen as to ensure the player doesn't clip through it:

1. Instead of reverting to its untilted state, the dripleaf would instead retain the tilted state it was in when it received power. This would either only remain until the player steps off it, or it could be permanent until power is removed; this latter option would have useful applications if a permanently-tilted dripleaf is desired.
2. The dripleaf would immediately revert to its untilted state, and the player would be moved up slightly to be on top of it. This is the approach that has been used to fix similar issues with changing block sizes, such as farmland/dirt paths reverting to dirt (MC-104259, MC-120611), and increasing stacks of turtle eggs (MC-129309).
3. The dripleaf would immediately revert to its untilted state, and due to the speed at which it moves back, the player on top would be launched upwards by it, similarly to a slime block moved by a piston.