Well aware that I know nothing about gdb, here's my first attempt. I've followed your instructions but I don't really see any useful output.

I answered yes to a question that I'm not sure I should have, however answering no to that question gives the same result, ie no backtrace (that I can see).

I have installed firefox-dbg before doing this.

osh@ardbeg:~$ firefox --sync &
[1] 25784
osh@ardbeg:~$ gdb /usr/lib/firefox/firefox-bin -p 25784
GNU gdb 6.4.90-debian
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i486-linux-gnu"...Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".

Attaching to program: /usr/lib/firefox/firefox-bin, process 25784
Reading symbols from /usr/lib/firefox/libmozjs.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libmozjs.so...done.
done.
Loaded symbols for /usr/lib/firefox/libmozjs.so
Reading symbols from /usr/lib/firefox/libxpcom.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libxpcom.so...done.
done.
Loaded symbols for /usr/lib/firefox/libxpcom.so
Reading symbols from /usr/lib/firefox/libxpcom_core.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libxpcom_core.so...done.
done.
Loaded symbols for /usr/lib/firefox/libxpcom_core.so
Reading symbols from /usr/lib/libplc4.so...Reading symbols from /usr/lib/debug/usr/lib/libplc4.so...done.
done.
Loaded symbols for /usr/lib/libplc4.so
Reading symbols from /usr/lib/libnspr4.so...Reading symbols from /usr/lib/debug/usr/lib/libnspr4.so...done.
done.
Loaded symbols for /usr/lib/libnspr4.so
Reading symbols from /lib/tls/i686/cmov/libpthread.so.0...done.
[Thread debugging using libthread_db enabled]
[New Thread -1220437120 (LWP 25784)]
[New Thread -1341588576 (LWP 25827)]
[New Thread -1332671584 (LWP 25823)]
[New Thread -1305011296 (LWP 25822)]
[New Thread -1313404000 (LWP 25818)]
[New Thread -1296618592 (LWP 25813)]
[New Thread -1286161504 (LWP 25809)]
[New Thread -1277768800 (LWP 25808)]
[New Thread -1269376096 (LWP 25807)]
[New Thread -1260639328 (LWP 25802)]
[New Thread -1242928224 (LWP 25799)]
[New Thread -1223443552 (LWP 25787)]
Loaded symbols for /lib/tls/i686/cmov/libpthread.so.0
Reading symbols from /usr/lib/libgtk-x11-2.0.so.0...done.
Loaded symbols for /usr/lib/libgtk-x11-2.0.so.0
Reading symbols from /usr/lib/libgdk-x11-2.0.so.0...done.
Loaded symbols for /usr/lib/libgdk-x11-2.0.so.0
Reading symbols from /usr/lib/libX11.so.6...done.
Loaded symbols for /usr/lib/libX11.so.6
Reading symbols from /usr/lib/libstdc++.so.6...done.
Loaded symbols for /usr/lib/libstdc++.so.6
Reading symbols from /lib/tls/i686/cmov/libc.so.6...done.
Loaded symbols for /lib/tls/i686/cmov/libc.so.6
Reading symbols from /lib/tls/i686/cmov/libm.so.6...done.
Loaded symbols for /lib/tls/i686/cmov/libm.so.6
Reading symbols from /usr/lib/libplds4.so...Reading symbols from /usr/lib/debug/usr/lib/libplds4.so...done.
done.
Loaded symbols for /usr/lib/libplds4.so
Reading symbols from /lib/tls/i686/cmov/libdl.so.2...done.
Loaded symbols for /lib/tls/i686/cmov/libdl.so.2
Reading symbols from /lib/libgcc_s.so.1...done.
Loaded symbols for /lib/libgcc_s.so.1
Reading symbols from /lib/ld-linux.so.2...done.
Loaded symbols for /lib/ld-linux.so.2
Reading symbols from /usr/lib/libgdk_pixbuf-2.0.so.0...done.
Loaded symbols for /usr/lib/libgdk_pixbuf-2.0.so.0
Reading symbols from /usr/lib/libpangocairo-1.0.so.0...done.
Loaded symbols for /usr/lib/libpangocairo-1.0.so.0
Reading symbols from /usr/lib/libpango-1.0.so.0...done.
Loaded symbols for /usr/lib/libpango-1.0.so.0
Reading symbols from /usr/lib/libatk-1.0.so.0...done.
Loaded symbols for /usr/lib/libatk-1.0.so.0
Reading symbols from /usr/lib/libgobject-2.0.so.0...done.
Loaded symbols for /usr/lib/libgobject-2.0.so.0
Reading symbols from /usr/lib/libgmodule-2.0.so.0...done.
Loaded symbols for /usr/lib/libgmodule-2.0.so.0
Reading symbols from /usr/lib/libglib-2.0.so.0...done.
Loaded symbols for /usr/lib/libglib-2.0.so.0
Reading symbols from /usr/lib/libcairo.so.2...done.
Loaded symbols for /usr/lib/libcairo.so.2
Reading symbols from /usr/lib/libfontconfig.so.1...done.
Loaded symbols for /usr/lib/libfontconfig.so.1
Reading symbols from /usr/lib/libXext.so.6...done.
Loaded symbols for /usr/lib/libXext.so.6
Reading symbols from /usr/lib/libXrender.so.1...done.
Loaded symbols for /usr/lib/libXrender.so.1
Reading symbols from /usr/lib/libXinerama.so.1...done.
Loaded symbols for /usr/lib/libXinerama.so.1
Reading symbols from /usr/lib/libXi.so.6...done.
Loaded symbols for /usr/lib/libXi.so.6
Reading symbols from /usr/lib/libXrandr.so.2...done.
Loaded symbols for /usr/lib/libXrandr.so.2
Reading symbols from /usr/lib/libXcursor.so.1...done.
Loaded symbols for /usr/lib/libXcursor.so.1
Reading symbols from /usr/lib/libXfixes.so.3...done.
Loaded symbols for /usr/lib/libXfixes.so.3
Reading symbols from /usr/lib/libXau.so.6...done.
Loaded symbols for /usr/lib/libXau.so.6
Reading symbols from /usr/lib/libXdmcp.so.6...done.
Loaded symbols for /usr/lib/libXdmcp.so.6
Reading symbols from /usr/lib/libpangoft2-1.0.so.0...done.
Loaded symbols for /usr/lib/libpangoft2-1.0.so.0
Reading symbols from /usr/lib/libfreetype.so.6...done.
Loaded symbols for /usr/lib/libfreetype.so.6
Reading symbols from /usr/lib/libz.so.1...done.
Loaded symbols for /usr/lib/libz.so.1
Reading symbols from /lib/tls/i686/cmov/librt.so.1...done.
Loaded symbols for /lib/tls/i686/cmov/librt.so.1
Reading symbols from /usr/lib/libpng12.so.0...done.
Loaded symbols for /usr/lib/libpng12.so.0
Reading symbols from /usr/lib/libexpat.so.1...done.
Loaded symbols for /usr/lib/libexpat.so.1
Reading symbols from /usr/lib/X11/locale/common/xlcUTF8Load.so.2...done.
Loaded symbols for /usr/lib/X11/locale/common/xlcUTF8Load.so.2
Reading symbols from /usr/lib/gconv/ISO8859-1.so...done.
Loaded symbols for /usr/lib/gconv/ISO8859-1.so
Reading symbols from /usr/lib/gconv/UTF-16.so...done.
Loaded symbols for /usr/lib/gconv/UTF-16.so
Reading symbols from /lib/tls/i686/cmov/libnss_files.so.2...done.
Loaded symbols for /lib/tls/i686/cmov/libnss_files.so.2
Reading symbols from /usr/lib/firefox/components/libbrowserdirprovider.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libbrowserdirprovider.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libbrowserdirprovider.so
Reading symbols from /usr/lib/firefox/components/libmyspell.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libmyspell.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libmyspell.so
Reading symbols from /usr/lib/libmyspell.so.3...done.
Loaded symbols for /usr/lib/libmyspell.so.3
Reading symbols from /usr/lib/firefox/components/libchrome.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libchrome.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libchrome.so
Reading symbols from /usr/lib/firefox/components/libpref.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libpref.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libpref.so
Reading symbols from /usr/lib/firefox/components/libnecko.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libnecko.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libnecko.so
Reading symbols from /usr/lib/firefox/components/libautoconfig.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libautoconfig.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libautoconfig.so
Reading symbols from /usr/lib/firefox/components/libi18n.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libi18n.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libi18n.so
Reading symbols from /usr/lib/firefox/components/libbrowsercomps.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libbrowsercomps.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libbrowsercomps.so
Reading symbols from /usr/lib/firefox/libgkgfx.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libgkgfx.so...done.
done.
Loaded symbols for /usr/lib/firefox/libgkgfx.so
Reading symbols from /usr/lib/firefox/libxpcom_compat.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libxpcom_compat.so...done.
done.
Loaded symbols for /usr/lib/firefox/libxpcom_compat.so
Reading symbols from /usr/lib/firefox/components/libxpconnect.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libxpconnect.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libxpconnect.so
Reading symbols from /usr/lib/firefox/components/libjar50.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libjar50.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libjar50.so
Reading symbols from /usr/lib/firefox/components/libwidget_gtk2.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libwidget_gtk2.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libwidget_gtk2.so
Reading symbols from /usr/lib/firefox/libgtkxtbin.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libgtkxtbin.so...done.
done.
Loaded symbols for /usr/lib/firefox/libgtkxtbin.so
Reading symbols from /usr/lib/libXt.so.6...done.
Loaded symbols for /usr/lib/libXt.so.6
Reading symbols from /usr/lib/libSM.so.6...done.
Loaded symbols for /usr/lib/libSM.so.6
Reading symbols from /usr/lib/libICE.so.6...done.
Loaded symbols for /usr/lib/libICE.so.6
Reading symbols from /lib/tls/i686/cmov/libnss_compat.so.2...done.
Loaded symbols for /lib/tls/i686/cmov/libnss_compat.so.2
Reading symbols from /lib/tls/i686/cmov/libnsl.so.1...done.
Loaded symbols for /lib/tls/i686/cmov/libnsl.so.1
Reading symbols from /lib/tls/i686/cmov/libnss_nis.so.2...done.
Loaded symbols for /lib/tls/i686/cmov/libnss_nis.so.2
Reading symbols from /usr/lib/gtk-2.0/2.10.0/engines/libqtengine.so...done.
Loaded symbols for /usr/lib/gtk-2.0/2.10.0/engines/libqtengine.so
Reading symbols from /usr/lib/libqt-mt.so.3...done.
Loaded symbols for /usr/lib/libqt-mt.so.3
Reading symbols from /usr/lib/libaudio.so.2...done.
Loaded symbols for /usr/lib/libaudio.so.2
Reading symbols from /usr/lib/libjpeg.so.62...done.
Loaded symbols for /usr/lib/libjpeg.so.62
Reading symbols from /usr/lib/libXft.so.2...done.
Loaded symbols for /usr/lib/libXft.so.2
Reading symbols from /usr/lib/kde3/plugins/styles/plastik.so...done.
Loaded symbols for /usr/lib/kde3/plugins/styles/plastik.so
Reading symbols from /usr/lib/libkdefx.so.4...done.
Loaded symbols for /usr/lib/libkdefx.so.4
Reading symbols from /usr/lib/firefox/components/libtoolkitcomps.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libtoolkitcomps.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libtoolkitcomps.so
Reading symbols from /usr/lib/firefox/components/libembedcomponents.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libembedcomponents.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libembedcomponents.so
Reading symbols from /usr/lib/firefox/components/libcaps.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libcaps.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libcaps.so
Reading symbols from /usr/lib/firefox/components/librdf.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/librdf.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/librdf.so
Reading symbols from /usr/lib/firefox/components/libdocshell.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libdocshell.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libdocshell.so
Reading symbols from /usr/lib/firefox/components/libsystem-pref.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libsystem-pref.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libsystem-pref.so
Reading symbols from /usr/lib/firefox/components/libappcomps.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libappcomps.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libappcomps.so
Reading symbols from /usr/lib/firefox/components/libnsappshell.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libnsappshell.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libnsappshell.so
Reading symbols from /usr/lib/libgconf-2.so.4...done.
Loaded symbols for /usr/lib/libgconf-2.so.4
Reading symbols from /usr/lib/libORBit-2.so.0...done.
Loaded symbols for /usr/lib/libORBit-2.so.0
Reading symbols from /usr/lib/libgthread-2.0.so.0...done.
Loaded symbols for /usr/lib/libgthread-2.0.so.0
Reading symbols from /usr/lib/firefox/components/libgklayout.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libgklayout.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libgklayout.so
Reading symbols from /usr/lib/firefox/components/libimglib2.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libimglib2.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libimglib2.so
Reading symbols from /usr/lib/firefox/components/libuconv.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libuconv.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libuconv.so
Reading symbols from /usr/lib/firefox/components/libhtmlpars.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libhtmlpars.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libhtmlpars.so
Reading symbols from /usr/lib/firefox/components/libcommandlines.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libcommandlines.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libcommandlines.so
Reading symbols from /usr/lib/firefox/components/libgfx_gtk.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libgfx_gtk.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libgfx_gtk.so
Reading symbols from /usr/lib/libpangoxft-1.0.so.0...done.
Loaded symbols for /usr/lib/libpangoxft-1.0.so.0
Reading symbols from /usr/lib/firefox/libgfxpsshar.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libgfxpsshar.so...done.
done.
Loaded symbols for /usr/lib/firefox/libgfxpsshar.so
Reading symbols from /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-xpm.so...done.
Loaded symbols for /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-xpm.so
Reading symbols from /usr/lib/firefox/components/libwebbrwsr.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libwebbrwsr.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libwebbrwsr.so
Reading symbols from /usr/lib/firefox/components/libpermissions.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libpermissions.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libpermissions.so
Reading symbols from /usr/lib/firefox/components/libcookie.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libcookie.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libcookie.so
Reading symbols from /usr/lib/firefox/components/libpipboot.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libpipboot.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libpipboot.so
Reading symbols from /usr/lib/firefox/components/liboji.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/liboji.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/liboji.so
Reading symbols from /usr/lib/firefox/libjsj.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libjsj.so...done.
done.
Loaded symbols for /usr/lib/firefox/libjsj.so
Reading symbols from /usr/lib/firefox/components/libremoteservice.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libremoteservice.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libremoteservice.so
Reading symbols from /usr/lib/firefox/components/libuniversalchardet.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libuniversalchardet.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libuniversalchardet.so
Reading symbols from /usr/lib/firefox/components/libeditor.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libeditor.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libeditor.so
Reading symbols from /usr/lib/firefox/components/libtxmgr.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libtxmgr.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libtxmgr.so
Reading symbols from /usr/lib/firefox/components/libspellchecker.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libspellchecker.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libspellchecker.so
Reading symbols from /usr/lib/firefox/components/libcomposer.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libcomposer.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libcomposer.so
Reading symbols from /usr/lib/firefox/components/libstoragecomps.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libstoragecomps.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libstoragecomps.so
Reading symbols from /usr/lib/firefox/components/libnecko2.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libnecko2.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libnecko2.so
Reading symbols from /lib/tls/i686/cmov/libnss_dns.so.2...done.
Loaded symbols for /lib/tls/i686/cmov/libnss_dns.so.2
Reading symbols from /lib/tls/i686/cmov/libresolv.so.2...done.
Loaded symbols for /lib/tls/i686/cmov/libresolv.so.2
Reading symbols from /usr/lib/firefox/components/libmork.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libmork.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libmork.so
Reading symbols from /usr/lib/firefox/components/libpipnss.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/components/libpipnss.so...done.
done.
Loaded symbols for /usr/lib/firefox/components/libpipnss.so
Reading symbols from /usr/lib/libsmime3.so...Reading symbols from /usr/lib/debug/usr/lib/libsmime3.so...done.
done.
Loaded symbols for /usr/lib/libsmime3.so
Reading symbols from /usr/lib/libssl3.so...Reading symbols from /usr/lib/debug/usr/lib/libssl3.so...done.
done.
Loaded symbols for /usr/lib/libssl3.so
Reading symbols from /usr/lib/libnss3.so...Reading symbols from /usr/lib/debug/usr/lib/libnss3.so...done.
done.
Loaded symbols for /usr/lib/libnss3.so
Reading symbols from /usr/lib/libsoftokn3.so...Reading symbols from /usr/lib/debug/usr/lib/libsoftokn3.so...done.
done.
Loaded symbols for /usr/lib/libsoftokn3.so
Reading symbols from /usr/lib/libfreebl3.so...Reading symbols from /usr/lib/debug/usr/lib/libfreebl3.so...done.
done.
Loaded symbols for /usr/lib/libfreebl3.so
Reading symbols from /usr/lib/firefox/libnssckbi.so...Reading symbols from /usr/lib/debug/usr/lib/firefox/libnssckbi.so...done.
done.
Loaded symbols for /usr/lib/firefox/libnssckbi.so
0xffffe410 in __kernel_vsyscall ()
(gdb) break gdk_x_error
Function "gdk_x_error" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (gdk_x_error) pending.
(gdb) continue
Continuing.
[Thread -1313404000 (LWP 25818) exited]
[Thread -1286161504 (LWP 25809) exited]
[Thread -1277768800 (LWP 25808) exited]
[Thread -1269376096 (LWP 25807) exited]
[Thread -1260639328 (LWP 25802) exited]
[New Thread -1260639328 (LWP 25965)]
[New Thread -1277768800 (LWP 25972)]
[New Thread -1286161504 (LWP 25973)]
[Thread -1260639328 (LWP 25965) exited]
[New Thread -1260639328 (LWP 25978)]
[Thread -1286161504 (LWP 25973) exited]
/bin/sh: /usr/bin/esd: not found
The program 'firefox-bin' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadMatch (invalid parameter attributes)'.
  (Details: serial 118 error_code 8 request_code 147 minor_code 3)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)

Program exited with code 01.
(gdb) thread apply all bt
(gdb) [1]+  Exit 1                  firefox --sync