The bug

Standing on the edge of a dripleaf and a honey block causes the dripleaf to wilt, even though the player is supported by the honey block.

How to reproduce

Place a Dripleaf and a honey block next to each other and stand so your hitbox is inside both blocks. The dripleaf will wilt, recover, and wilt again endlessly. No change in your feet coordinate occurs, so the dripleaf is not supporting you at all.