This was precisely what I’d envisioned, before I noticed the way that Acci had already handled the case of focused-character travel.
Honestly, I think it’s fine as it is. The mutes prevent visual clutter produced by folks zipping around, but it makes sense from both IC and UX perspectives that I’d see the movement of a character I’m paying attention to as an action described in detail.
I think I have called them “mute placeholders”, or “placeholders for muted messages”.
I think that a focused character shouldn’t get muted. But I also will do colored mute pills… erm… placeholders.
Focus and mute works on different levels.
Focus works retroactively on all messages, while mute does not. When muting is activated, the decision whether to mute a message or not is made when the message arrives to the client. This is stored as additional info together with the event in the browser’s DB.
That allows us to reload the client and still keep the same messages muted.
But it also means we might activate focus later on for a character whose travel messages has previously been muted. In this case, I will do the “colored pill” thing you suggest. 
I’ve enjoyed the feature so far. But it is rather amusing to me how people’s travel messages in a small room get announced with a single plip. Maybe only stack the messages when there’s more then one on a line. A one plip line takes same space.
Ha! That’s a good point. It is kind of funny when you’re expecting someone in a private (or public-but-sparse) space, and their arrival is just [blat]. I suppose you could always focus on 'em first, to avoid that effect.
I kinda like the idea of something like Halstrick arrives from the east. when I show up right after some dialog, and letting it morph to ◽️◽️ if someone comes in right afterwards, or if I zoom away in the next moment.