pool #31881 is categorised as a "series". It’s not a comic or sequence, so I think categorisation isn’t very fitting.

However, I get an error message when trying to change that. It says I can’t change the category because the pool has more than 30 posts.

dimoretpinel said:
pool #31881 is categorised as a "series". It’s not a comic or sequence, so I think categorisation isn’t very fitting.

However, I get an error message when trying to change that. It says I can’t change the category because the pool has more than 30 posts.

Yeah that's intended to protect against vandalism
It's only purpose is to filter pools and nobody cares about the feature so it's not going to be effective in that task