These aren’t really similar, though it may be unclear depending on the types of notifications you current have. “All notifications” is a combination of all the different notification types — it’s the primary notification feed.
“Other notifications” is for certain types of notifications that don’t fit into other filters (things like badges, edits, links, solutions).
Of course, the fact that you didn’t know that isn’t your fault and may be something we can work on clarifying.
Yeah we have some ideas for how to unify the navigation a little bit, hopefully we can get to them soon. I think messages and direct chats are a little redundant, but we have a lot of functionality tied to messages (email inboxes, moderation) and chat is optional… so we’re going to have both for the foreseeable future.
fortunately this is an easy one, the icons will all be unique after this is merged UX: make all preference icons unique by awesomerobot · Pull Request #33202 · discourse/discourse · GitHub
Thanks for the feedback!