Description of problem:
1) Right clicked on Cinnamon panel
2) selected "configure panel"
3) changed something - i don't remember what and can't go back and do it again to refresh my memory
4) an error message flashed up briefly about cinnamon config crashing or something - went away before i could read it properly
6) right clicked panel again
7) selected "configure panel"
8) selected "Classic" (panel top and bottom)
9) X slowly ground to a halt
10) no input working - ctrl-alt-F2 not working
11) waited a while, but still nothing
12) forced power off by holding down power button
13) rebooted
14) now cinnamon desktop is blank. mouse pointer moves, but nothing else on screen, right click doesn't work
15) couldn't log off, so killed Xorg (via ctrl-alt-F2 etc)
16) tried again. waited a while to see if cinnamon desktop would do anything else. it didn't.
17) killed Xorg again and logged in using mate. no problems with mate desktop


Version-Release number of selected component:
mate-panel-1.5.6-1.fc18

Additional info:
backtrace_rating: 4
cmdline:        mate-panel
crash_function: g_type_check_instance_is_a
executable:     /usr/bin/mate-panel
kernel:         3.8.11-200.fc18.x86_64
uid:            1000
ureports_counter: 1
xsession_errors: 

Truncated backtrace:
Thread no. 1 (10 frames)
 #0 g_type_check_instance_is_a at gtype.c:3964
 #1 gtk_widget_get_parent at gtkwidget.c:6483
 #2 mate_panel_applet_get_panel_widget at applet.c:48
 #3 mate_panel_applet_locked_change_notify at applet.c:192
 #4 g_cclosure_marshal_VOID__STRINGv at gmarshal.c:1004
 #5 _g_closure_invoke_va at gclosure.c:840
 #8 g_settings_real_change_event at gsettings.c:288
 #9 ffi_call_unix64 at ../src/x86/unix64.S:75
 #10 ffi_call at ../src/x86/ffi64.c:486
 #11 g_cclosure_marshal_generic_va at gclosure.c:1550