fixed event/live transition

README.md

@@ -583,6 +583,22 @@ A replay leaves trigger mode, because a file has no edge to wait for -- an armed
 held display draws that snapshot rather than the file that was just loaded. The events pane stays
 open through it: it is available while a stored event is on screen.
 
+**Going back to *Live* puts the live view back as it was.** Opening a file changes two things that
+are not the user's choice -- the time window becomes the event's own span, because that is what
+framing an event means, and trigger mode goes off for the reason above -- and neither reason survives
+the way back. So the settings the live view had are taken on the way in and restored on the way out:
+the time window, trigger mode, the trigger's channel, level, condition, pre-trigger share and
+hold-off. The trigger's channel is remembered by **name**, since a comparison renames its channels
+(`square (A)`) and the way back has to find the stream's own. The restore waits for the first CONFIG
+of the restarted client, which is a frame or two, and is the last word on the window -- it was
+previously the *saved* session's window that came back, which is to say, somebody else's.
+
+A related repair: **the session file is no longer written while a stored event is on screen.** A
+comparison rebinds every plot slot to its own renamed channels, and the automatic save wrote those
+names into the session -- so the next *Live* re-applied a layout that named no live signal, and the
+scope came back with an empty plot. Nothing is lost by skipping: a file view configured nothing about
+the stream. The explicit *Save as* is unaffected; that one is an answer to a question the user asked.
+
 Three things worth knowing:
 
 - **The samples are the export format**, so an event is readable by everything that reads an
@@ -1181,7 +1197,9 @@ row's `×` forgets a source by deleting its session file, with no confirmation:
 confirmation, and what it destroys is one layout the app rewrites on the next clean exit. A session
 is **not written** when no CONFIG arrived during the run — otherwise a source whose streamer was
 down during one launch would silently vanish from the chooser list because its file was flattened
-to empty signal names, which the filter refuses.
+to empty signal names, which the filter refuses — nor while a **stored event is on screen**, for
+the same reason stated the other way round: a file view configured nothing about the stream, and a
+comparison's renamed slots written into the session came back as an empty plot.
 
 **Math channels.** A math channel is derived from the others by a graph of operations and is then
 an *ordinary channel*: the model synthesises a signal entry for it, so an enabled one is acquired,