Comment 7 for bug 2012116

It's a bug in libtimezonemap, it's easier to trigger by using this in the ubiquity source

$ ./plugin-viewer-gtk.py ubi-timezone

it's probably another bug which existed but got more visible with https://gitlab.gnome.org/GNOME/glib/-/issues/2937

==124819== Invalid free() / delete / delete[] / realloc()
==124819== at 0x484620F: free (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==124819== by 0x650B13B: g_slice_free_chain_with_offset (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.7600.0)
==124819== by 0x1119CDB7: get_loc_for_xy (cc-timezone-map.c:942)
==124819== by 0x1119D66C: button_press_event (cc-timezone-map.c:961)
==124819== by 0x7C9B916: _gtk_marshal_BOOLEAN__BOXED (gtkmarshalers.c:84)
==124819== by 0x65EA00F: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.7600.0)

reassigning the report to the library