Cancelling on inventory click not consistent

Description

Placing an item into a slot that is set to be cancelled will eventually place the item where it shouldn't go. The does not seem to happen if an item already exists there.

Steps to Reproduce

on inventory click:
    if clicked slot is 5:
        cancel event

Expected Behavior

Cancel consistently

Errors / Screenshots

https://gyazo.com/a80d2695b485264b5722e4aff00ce0b7

Tested on

Minecraft: 1.14.4
Spigot: git-Spigot-56f8471-6567017 (MC: 1.14.4)
PaperMC: 234
Skript: 2.4 Stable

[Jayderp]

Hmm...

@Jayderp Github doesn't like you.

[bensku]

I have marked a few short comments that do not add any value here as spam. Please stop cluttering the issue tracker.

[TPGamesNL]

Duplicate of #3744.
Inventory drag events are called instead of inventory click events when the item is being dragged, and an item being dragged across 2 pixels in the same slot already counts as dragging, which doesn't call the inventory click event.