1) 1.14+ Added an option to the Villager Trade Cheesing Protection to allow server owners to limit the number of times between villager restocks. This is because there's a vanilla bug in 1.14 that allows villagers to restock nearly instantly multiple times per day.
https://bugs.mojang.com/browse/MC-157136
This bug is listed as fixed however no update has been pushed out yet, so we may not see the fix until 1.15!
2) Added support for two 3rd party shop plugins, (DynamicShops and CraftingStore) IllegalStack will ignore these plugins breaking the Over vanilla stack limits in their GUI's as they don't actually give players IllegalStacks of the item they only use them as a visual representation.
3) (1.11+ ONLY) Added a fix for users being able to bring items with unnatural NBT data from a single player world into a Multiplayer world (provided they had access to gamemode creative) This fix is only really relevant if you have players with access to GMC but NOT /give, players could still use /give to bring in items with funky NBT data if they have access to it.