To add to this and maybe help the process of solving the problem… I have noticed that it doesn’t happen for my custom taxonomies (at least it appears to not be happening anyway). From what I have seen, it only happens for fields created for Categories.
If it starts happening to my custom taxonomies I’ll definitely post an update here.
And, no replies yet? 2 months later?? Weird, hehe. Here’s hoping a solution is coming in the near future.