Thank you very much! So I was correct in understanding that there is padding.
While this padding is required for building a tensor, it is quite misleading to see repeats. Updated the example in docs with your example above would be really really really helpful.
For my use case, I will stick to my implementation then as there is no way but to use a loop to avoid padded duplicates. This is mostly because I need the ordered unique. However, the alternative would be to get the relative indices and then shuffle.