One fork in the undo is worth deciding now: how it is implemented. If it publishes a deletion event, relays are only asked to honour it. Some keep the repost, and a client that already cached it shows it anyway. A local ignore list is the only version that looks the same in every client. The reactions toggle has a similar fork: a second subscription to reaction events from everyone you follow, or a render of what your client already fetches. The first costs bandwidth on every timeline load, the second is free. Which of the two is it?