Quick answer
A run does not happen in your browser. It is queued and executed away from the page, so you can move around the job, close the tab or sign out and come back to a finished step. The banner tells you which it is doing: waiting in line, or running with the elapsed time.
What the banner is telling you
"starts in about a minute" or "is in line to start and begins automatically": the run is queued behind other work. Nothing is needed from you.
"is starting up, this can take a few minutes outside office hours": capacity is warming up. It will start.
"AllDone is running" with a seconds or minutes count: it is executing. Most steps are quick; a records check on a large job with scanned documents is the slow one.
"finished, this page has been updated": it landed and the screen has refreshed itself.
Your own click always takes priority over work AllDone started for itself, such as a re-run triggered by a decision, so you never wait behind a background job.
Things that are working as intended
"Already running for this job." Two runs on one job would write over each other's working papers, so the second is refused rather than risked. The message says whether it was your own click, your own decision's automatic re-run, or a colleague. Wait for it; the page follows it.
Nothing on screen after a reload. Reload again or revisit the job. The page re-attaches to a run in progress rather than losing it. The page stops watching after a long wait, which does not cancel anything.
When to worry
If a run stops reporting back it is marked as abandoned rather than left saying "running" for ever, and you are told. Run it again: nothing is left half applied, because a run's changes are written together or not at all. The same is true of a run that could not be completed after being retried.
If a step stops early on purpose, the block under the step row names the step it stopped at. Read that step's messages before re-running; something in the records needs an answer rather than another attempt.
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