Seems to be an upstream issue. I went digging for a while and the problem was coming from the GTKFileSystemModel's gtk_file_system_model_monitor_change G_FILE_MONITOR_EVENT_DELETED event. The event is triggered from the g_unlink(ft) on line 328 in themer/main.c, although it isn't the unlinking itself that causes the problem.
The file system model apparently recently underwent some updates, one of which seemed to be fixing this issue. I compiled and installed the lastest GTK+ from SVN and the problem went away, no more crashes.
Seems to be an upstream issue. I went digging for a while and the problem was coming from the GTKFileSystemMo del's gtk_file_ system_ model_monitor_ change G_FILE_ MONITOR_ EVENT_DELETED event. The event is triggered from the g_unlink(ft) on line 328 in themer/main.c, although it isn't the unlinking itself that causes the problem.
The file system model apparently recently underwent some updates, one of which seemed to be fixing this issue. I compiled and installed the lastest GTK+ from SVN and the problem went away, no more crashes.