Comment 2 for bug 1724858

StacktraceTop:
 g_assertion_message (domain=domain@entry=0x7f986e9ffc9b "GLib-GObject", file=file@entry=0x7f986ea01eee "../../../../gobject/gobject.c", line=line@entry=4429, func=func@entry=0x7f986ea02f48 <__func__.13872> "g_weak_ref_set", message=message@entry=0x55b1352700f0 "assertion failed: (weak_locations != NULL)") at ../../../../glib/gtestutils.c:2436
 g_assertion_message_expr (domain=domain@entry=0x7f986e9ffc9b "GLib-GObject", file=file@entry=0x7f986ea01eee "../../../../gobject/gobject.c", line=line@entry=4429, func=func@entry=0x7f986ea02f48 <__func__.13872> "g_weak_ref_set", expr=expr@entry=0x7f986ea0236d "weak_locations != NULL") at ../../../../glib/gtestutils.c:2459
 g_weak_ref_set (weak_ref=weak_ref@entry=0x7f984824ab70, object=object@entry=0x0) at ../../../../gobject/gobject.c:4429
 g_weak_ref_clear (weak_ref=0x7f984824ab70) at ../../../../gobject/gobject.c:4332
 g_settings_backend_invoke_closure (user_data=0x55b13539a600) at ../../../../gio/gsettingsbackend.c:275