A reused command pane leaves the last program's screen modes before the next command

A program that crashed out of a full screen left the command pane's emulator
in the alternate screen with mouse reports, bracketed paste or a hidden cursor
on, and the next command ran in that. Before the '% line' separator the pane
now leaves the alternate screen, turns those modes off and soft-resets
(DECSTR). The docs add that a command which clears the screen and its
scrollback erases the pane's history above it.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 4 insertions, 1 deletions

diff --git a/docs/fs.md b/docs/fs.md
index 3efc5b36..ebc85f12 100644
--- a/docs/fs.md
+++ b/docs/fs.md
@@ -240,7 +240,10 @@ same tree without leaving the process.
   which shows its output and then `exit N` (its tag reads `<dir> (<line>)
   running`, then `exit N`), and stays. The directory's next command runs in
   that pane once it is done, below what it showed, after a `% <line>` line;
-  one still running gets a second pane. A command pane's own exec starts
+  one still running gets a second pane. Before the next command the pane
+  leaves any alternate screen and turns off the modes a program left on
+  (mouse reports, bracketed paste, a hidden cursor); a command that clears
+  the screen and its scrollback (`clear`, ED3) erases the history above it. A command pane's own exec starts
   the next command there too. The log says `run <serial> <word>` and `exit
   <serial> <N|?>`; `exec` reads back the command pane's serial; Kill ends
   its whole process group; a line is at most 1 KB. A misspelled word is a