Anvilling a enchantment book with a wand item with said enchant present already does not allow you to combine enchantments

[I0nTech]

For example, you have a magic sword wand with sharpness 3 on it - if you anvil it with another sharpness 3 book, it will not allow you to remove it from the anvil GUI. However if you anvil it with a sharpness 4 book, it will allow you to remove it.

Demonstration attached below to reproduce steps: https://youtu.be/-LyXinAavGQ

Would appreciate if this was fixed, was causing a lot of confusion.