Firefox freezes when using “save as” (glib issue?)

When trying to save anything in Firefox, using “save as” to do so, when the dialog box starts to show up, everything turns gray for a moment and then Firefox freezes permanently. Running firefox on gdb, I receive these error messages: > [Parent 9504, Main Thread] ###!!! ASSERTION: No GSettings schemas are installed on the system: ‘glib assertion’, file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:184 > (firefox:9504): GLib-GIO-ERROR **: No GSettings schemas are installed on the system > Thread 1 received signal SIGTRAP, Trace/breakpoint trap. > g_logv (log_domain=0x7ffff1c42238 “GLib-GIO”, log_level=G_LOG_LEVEL_ERROR, format=, args=args@entry=0x7fffffff9cd8) at gmessages.c:1046 > 1046 gmessages.c: No such file or directory. Backtrace result: > #0 g_logv (log_domain=0x7ffff1c42238 “GLib-GIO”, log_level=G_LOG_LEVEL_ERROR, format=, args=args@entry=0x7fffffffa708) at gmessages.c:1046 > #1 0x00007ffff0dc9402 in g_log (log_domain=log_domain@entry=0x7ffff1c42238 “GLib-GIO”, log_level=log_level@entry=G_LOG_LEVEL_ERROR, format=format@entry=0x7ffff1c60cf8 “No GSettings schemas are installed on the system”) at gmessages.c:1079 > #2 0x00007ffff1bfe6b2 in g_settings_set_property (object=, prop_id=, value=0x7fffffffa850, pspec=) at gsettings.c:476 > #3 0x00007ffff12d0a79 in object_set_property (nqueue=0x7fffd7efca10, value=, pspec=0x7fffce9a53c0, object=0x7fffdded6900) at gobject.c:1415 > #4 g_object_new_internal (class=class@entry=0x7fffcd59a6d0, params=params@entry=0x7fffffffa980, n_params=n_params@entry=1) at gobject.c:1808 > #5 0x00007ffff12d24fd in g_object_new_valist (object_type=object_type@entry=140736916656768, first_property_name=first_property_name@entry=0x7ffff1c6087f “schema-id”, var_args=var_args@entry=0x7fffffffaac8) at gobject.c:2034 > #6 0x00007ffff12d27b4 in g_object_new (object_type=140736916656768, first_property_name=0x7ffff1c6087f “schema-id”) at gobject.c:1617 > #7 0x00007ffff551174c in ?? () from /arquivos/Gtk±3.14.0/lib/libgtk-3.so.0 > #8 0x00007ffff5513e50 in ?? () from /arquivos/Gtk±3.14.0/lib/libgtk-3.so.0 > #9 0x00007ffff550f744 in ?? () from /arquivos/Gtk±3.14.0/lib/libgtk-3.so.0 > #10 0x00007ffff12cb385 in g_closure_invoke (closure=0x7fffcdb80c60, return_value=0x0, n_param_values=1, param_values=0x7fffffffae60, invocation_hint=0x7fffffffae00) at gclosure.c:768 > #11 0x00007ffff12dd11c in signal_emit_unlocked_R (node=node@entry=0x7fffcc2fc520, detail=detail@entry=0, instance=instance@entry=0x7fffca161fb0, emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7fffffffae60) at gsignal.c:3553 > #12 0x00007ffff12e5d95 in g_signal_emit_valist (instance=instance@entry=0x7fffca161fb0, signal_id=signal_id@entry=291, detail=detail@entry=0, var_args=var_args@entry=0x7fffffffb030) at gsignal.c:3309 > #13 0x00007ffff12e64aa in g_signal_emit_by_name (instance=0x7fffca161fb0, detailed_signal=0x7ffff5717393 “default-size-changed”) at gsignal.c:3405 > #14 0x00007ffff5518c41 in ?? () from /arquivos/Gtk±3.14.0/lib/libgtk-3.so.0 > #15 0x00007ffff12d350b in object_set_property (nqueue=0x7fffcb20e890, value=0x7fffffffb250, pspec=0x7fffcbad19a0, object=0x7fffca161fb0) at gobject.c:1415 > #16 g_object_set_property (object=0x7fffca161fb0, property_name=, value=0x7fffffffb250) at gobject.c:2363 > #17 0x00007ffff12d0add in object_set_property (nqueue=0x7fffcb20e7c0, value=0x7fffffffb2b0, pspec=0x7fffcbad19a0, object=0x7fffcccd0670) at gobject.c:1415 > #18 g_object_new_internal (class=class@entry=0x7fffcf104f00, params=params@entry=0x7fffffffb390, n_params=n_params@entry=2) —Type to continue, or q to quit— at gobject.c:1828 > #19 0x00007ffff12d24fd in g_object_new_valist (object_type=object_type@entry=140736584521760, first_property_name=first_property_name@entry=0x7ffff56fe920 “title”, var_args=var_args@entry=0x7fffffffb4d8) at gobject.c:2034 > #20 0x00007ffff12d27b4 in g_object_new (object_type=140736584521760, first_property_name=0x7ffff56fe920 “title”) at gobject.c:1617 > #21 0x00007ffff550fac5 in gtk_file_chooser_dialog_new () from /arquivos/Gtk±3.14.0/lib/libgtk-3.so.0 > #22 0x00007fffeec71630 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #23 0x00007fffeec70588 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #24 0x00007fffeabcb16e in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #25 0x00007fffeabc97c2 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #26 0x00007fffeabc887b in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #27 0x00007fffeac706c0 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #28 0x00007fffeaba671a in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #29 0x00007fffeb8bf375 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #30 0x00007fffeaba6304 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #31 0x00007fffeb4a8e6c in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #32 0x00007fffeb4a3d7e in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #33 0x00007fffeb4a1c95 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #34 0x00007fffec8d0eda in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #35 0x00007fffec527b01 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #36 0x00007fffebe31fa9 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #37 0x00007fffebdf20d7 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #38 0x00007fffebdf1198 in ?? () from /media/34GB/Arquivos-de-Programas-Linux/firefox/libxul.so > #39 0x00007ffff804efa6 in ?? () > #40 0x00007ffff6ddae70 in __libc_start_main (main=0x7ffff804ed00, argc=1, argv=0x7fffffffe2e8, init=, fini=, rtld_fini=, stack_end=0x7fffffffe2d8) at libc-start.c:269 > #41 0x00007ffff8062777 in _start ()