This bug is similar
MC-83064 where the player takes cumulative fall damage when using the levitation effect. If the player takes fall damage after having any levitation effect, the player will be launched into the air. I originally found this out while using downwards levitation effects, but after further testing, it happens with all levitation effects.
Video: https://www.youtube.com/watch?v=i9Y7i3737gw You can see that at the end of my death, I jump way up into the air. The flint is just used to give me levitation 2 when I have it in my offhand.
Steps to reproduce:
1. Find a place to fall
2. Effect yourself with any levitation effect (I have mainly tested with 2, 254, and 255) (/effect @p minecraft:levitation 10 1 (This will give you levitation 2 for 10 seconds))
3. Get over the falling area
4. Fall and bounce!