Disable player falling

I want to make it so that in Minecraft, whenever a player falls, they have a fall speed of 0, stopping them from falling. Can I do that in vanilla, and if not is there any way to do it with plugins?

Solution 1:

This is achievable in Vanilla Minecraft, without the usage of any game modifications, using a bug with the levitation effect:

Run /effect give <player> minecraft:levitation 1000000 255 true. You can restore gravity by running /effect clear <player> minecraft:leviation.

Unfortunately, this means you cannot jump at all, but it has quite an interesting effect, and movement works like a slower version of Creative Mode flight: