Description of problem:
Searching for 'wireshark'. Couldn't reproduce it on another try.

Version-Release number of selected component:
gnome-software-3.13.90-1.fc21

Additional info:
reporter:       libreport-2.2.3
backtrace_rating: 4
cmdline:        /usr/bin/gnome-software --gapplication-service
crash_function: g_type_check_instance_is_fundamentally_a
executable:     /usr/bin/gnome-software
kernel:         3.16.1-301.fc21.x86_64
runlevel:       N 5
type:           CCpp
uid:            1001

Truncated backtrace:
Thread no. 1 (10 frames)
 #0 g_type_check_instance_is_fundamentally_a at gtype.c:3979
 #1 g_param_spec_unref at gparam.c:229
 #2 gtk_style_context_clear_property_cache at gtkstylecontext.c:298
 #3 gtk_style_context_clear_cache at gtkstylecontext.c:2866
 #4 _gtk_style_context_validate at gtkstylecontext.c:3052
 #16 gtk_container_idle_sizer at gtkcontainer.c:1739
 #17 _g_closure_invoke_va at gclosure.c:831
 #19 g_signal_emit_by_name at gsignal.c:3405
 #20 gdk_frame_clock_paint_idle at gdkframeclockidle.c:408
 #26 g_main_context_iteration at gmain.c:3795