Weird occurrence

[Anthony Quas]

This bug report will be sent to the Free Software Foundation,
 not to your local site managers!!
Please write in English, because the Emacs maintainers do not have
translators to read other languages for them.

In GNU Emacs 20.7.1 (i386-redhat-linux-gnu, X toolkit)
 of Thu Aug 24 2000 on porky.devel.redhat.com
configured using `configure  --mandir=/usr/share/man --infodir=/usr/share/info 
--prefix=/usr --libexecdir=/usr/lib --sharedstatedir=/var --with-gcc --with-pop 
--with-x-toolkit i386-redhat-linux-gnu'

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

I have no idea what happened! I think I typed something but don't know
what. Suddenly, I could see only the first couple and last couple of
lines of the file (it was 990 lines long). Repeatedly pressing undo
did not change the situation.
What was stranger was that the line counter at the bottom of the
screen still reported the correct line numbers and I could use the
cursor keys to move up through the file without seeing it.
I pressed C-l to redraw the screen but it didn't show anything....
Did I suddenly put it in some weird mode??? I certainly couldn't
detect any kind of explanation.... After doing this, I quit and
started editing an old version of the file and everything seems fine
again. 

Sorry not to be able to be more specific.

Recent input:
menu-bar help-menu report-emacs-bug

Recent messages:
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