Enchantment table is giving extra enchantments, including ones that it is not supposed to at all (like silk touch).
What I expected to happen was...:
One enchantment is listed, I click it, I expect one enchantment to be added to my item.
What actually happened was...:
After enchanting, extra enchantments started appearing on my items such as riptide, silk touch, and more. The first image I am attaching is of a stone pickaxe I enchanted (just to reset enchants for a better one) with either efficiency or unbreaking (I don't remember which one it was originally), and then getting silk touch, efficiency IV and unbreaking III on it. The second is of a book that I enchanted with sharpness III but that also happened to get riptide III for some reason. Lastly is a video where I try to reproduce the issue. First doesn't work, but second time I enchant with efficiency I but also get unbreaking I. Video is linked here due to file size: https://www.dropbox.com/t/XF11dHznKP3QquWM
Steps to Reproduce:
I'm not sure if the bug will happen for others but as you can see I have simply been enchanting books and stone pickaxes, I've been between level 20 and 40 and using the grindstone occasionally.
not a bug, this is just how enchanting works. sometimes you get more than one enchantment on an item when enchanting through a table.