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Thread 1 (Thread 5128):
#0  0x00007f7e1cadf3c1 in strlen () from /lib/libc.so.6
No symbol table info available.
#1  0x00007f7e1edabe88 in gnome_desktop_thumbnail_factory_save_thumbnail ()
   from /usr/lib/libgnome-desktop-2.so.11
No symbol table info available.
#2  0x00007f7e1edaf01a in ?? () from /usr/lib/libgnome-desktop-2.so.11
No symbol table info available.
#3  0x00007f7e1edaf093 in ?? () from /usr/lib/libgnome-desktop-2.so.11
No symbol table info available.
#4  0x00007f7e1edb0f56 in ?? () from /usr/lib/libgnome-desktop-2.so.11
No symbol table info available.
#5  0x00007f7e1edb11dc in gnome_bg_create_thumbnail ()
   from /usr/lib/libgnome-desktop-2.so.11
No symbol table info available.
#6  0x000000000041f521 in gnome_wp_item_get_frame_thumbnail (item=0x2625700, 
    thumbs=0x2102f00, frame=-1) at gnome-wp-item.c:223
        pixbuf = <value optimized out>
        aspect = 0
#7  0x0000000000413fb5 in wp_props_load_wallpaper (key=<value optimized out>, 
    item=0x2625700, data=0x2105710) at appearance-desktop.c:156
        iter = {stamp = 745837619, user_data = 0x2438960, 
          user_data2 = 0x28648a0, user_data3 = 0x2102f00}
        path = <value optimized out>
        pixbuf = <value optimized out>
#8  0x00000000004140eb in wp_add_image (data=0x2105710, 
    filename=0x28648a0 "Firefox_wallpaper.png") at appearance-desktop.c:199
        item = <value optimized out>
#9  0x0000000000414413 in wp_load_stuffs (user_data=<value optimized out>)
    at appearance-desktop.c:936
        data = 0x2105710
        imagepath = 0x28648a0 "Firefox_wallpaper.png"
        uri = <value optimized out>
        style = <value optimized out>
        item = 0x0
#10 0x00007f7e1ce0abbe in g_main_context_dispatch ()
   from /lib/libglib-2.0.so.0
No symbol table info available.
#11 0x00007f7e1ce0e588 in ?? () from /lib/libglib-2.0.so.0
No symbol table info available.
#12 0x00007f7e1ce0e9e5 in g_main_loop_run () from /lib/libglib-2.0.so.0
No symbol table info available.
#13 0x00007f7e1e48d177 in gtk_main () from /usr/lib/libgtk-x11-2.0.so.0
No symbol table info available.
#14 0x0000000000418b63 in main (argc=1, argv=0x7fff265ccb08)
    at appearance-main.c:232
        w = <value optimized out>
        install_filename = 0x0
        start_page = 0x0
        wallpaper_files = 0x0
        option_context = <value optimized out>
        option_entries = {{long_name = 0x42faf8 "install-theme", 
            short_name = 105 'i', flags = 2, arg = G_OPTION_ARG_FILENAME, 
            arg_data = 0x7fff265cc9f8, 
            description = 0x42fbd8 "Specify the filename of a theme to install", arg_description = 0x42fb06 "filename"}, {long_name = 0x42fb0f "show-page", 
            short_name = 112 'p', flags = 2, arg = G_OPTION_ARG_STRING, 
            arg_data = 0x7fff265cc9f0, 
            description = 0x42fc08 "Specify the name of the page to show (theme|background|fonts|interface)", arg_description = 0x42fb14 "page"}, {
            long_name = 0x43138c "", short_name = 0 '\000', flags = 2, 
            arg = G_OPTION_ARG_FILENAME_ARRAY, arg_data = 0x7fff265cc9e8, 
            description = 0x0, arg_description = 0x42fb19 "[WALLPAPER...]"}, {
            long_name = 0x0, short_name = 0 '\000', flags = 0, 
            arg = G_OPTION_ARG_NONE, arg_data = 0x0, description = 0x0, 
            arg_description = 0x0}}