Sometimes it happens that an owner that wants to troll the channel unpins an important message from a chat list.
It happened at least two times in total now, for the C++ Channel. This is frustrating, because an owner that previously pinned a message can't pin it again, apparently.
Please show who unpinned or pinned a message, so that such users can be identified and the reason can be discussed. It's not like unpinning is an act like voting. Unpinning messages has a global effect to the whole channel; not showing the unpinner is a major present for trolls.