Review the newnym error handling UX
In #40926 (closed) we modularized the new identity, but we still have a torbutton part to clear domain isolation nonces and send a newnym to little-t-tor.
Clearing the nonces always works, whereas the newnym command might fail, for example little-t-tor died.
However, the current implementation check whether we have a valid configuration (sorta), otherwise it tries to send the command.
Both the branches have a problem.
To arrive to the former, a lot of other things must have failed before, so I don't think we'll need to add errors here.
But for reference, here is what it looks like currently:
The tor-died case is never handled, because we wait forever for a connection, or maybe we go to timeout after such a long time that I haven't seen the case.
The strings should be the same, and it seems an old one, still here from the days of torbutton as an extension.
We could change the alert with a modern dialog, but I'm not sure it'd be worth it.
Also, I'm exploring what the behavior is like, with my latest changes to this part of code.