Until now an installation took the newest published build and only found out during start-up whether every plugin it has installed was actually published for it. When one was not, the new version refused to come up and the update stalled — after the fact, and with the previous version still serving.
An installation now asks the question the other way round: which is the latest release that ships all of my plugins? It rolls to that one, so a build that is missing a package is simply passed over instead of being started and refused. When no published release ships everything, nothing is selected and the missing plugin is named rather than left for someone to find in a log.
Two things follow from the same change. An installation that cannot see its own plugin list no longer treats that as "nothing to check" and quietly takes the newest build — it stops and says so. And anyone rolling a version by hand, or from a delivery pipeline, can now ask an installation which release it should be on rather than only whether a version they already picked is safe.