mesh/merge-gate pass: builds new: modules/betterbird, sent nowhere; no bus step; every machine composes with the change as it did without (4 of 4 compose)
A restart ended Betterbird with whatever a composer held; now it refuses while a Msgcompose window is
open unless discard_unsent says the operator agreed, and answers within the runtime's 30 s. A
preference's value could carry an address, a user%40domain@host URI, a host or the home; those are
masked, recent-folder, account and cloud-file preferences and every add-on preference but the theme's
id are withheld, and a request for everything is refused. A log kept the token after Bearer or Basic.
The reminder test's Betterbird counted as the operator's and left its profile behind when it ended on
its own; it is now left out everywhere and its unit removes the profile when it stops.
