$ gdb --args shotwell -d .shotwell_test
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Reading symbols from shotwell...Reading symbols from /usr/lib/debug/.build-id/7c/fe88e22267cf3f8bc4c968ff746d24abbe007c.debug...done.
done.
(gdb) r
Starting program: /usr/bin/shotwell -d .shotwell_test
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffe6204700 (LWP 12727)]
[New Thread 0x7fffe5a03700 (LWP 12728)]
[New Thread 0x7fffe4a67700 (LWP 12729)]
[New Thread 0x7fffcfa6b700 (LWP 12730)]
[New Thread 0x7fffc955d700 (LWP 12731)]
[New Thread 0x7fffc8d5c700 (LWP 12732)]
[New Thread 0x7fffc855b700 (LWP 12733)]
[New Thread 0x7fffc7d5a700 (LWP 12734)]
[New Thread 0x7fffc6e7c700 (LWP 12735)]
[New Thread 0x7fffc667b700 (LWP 12736)]
[Thread 0x7fffc667b700 (LWP 12736) exited]
[New Thread 0x7fffc667b700 (LWP 12738)]
[Thread 0x7fffc667b700 (LWP 12738) exited]
[New Thread 0x7fffc667b700 (LWP 12739)]
[Thread 0x7fffc667b700 (LWP 12739) exited]
[New Thread 0x7fffc667b700 (LWP 12740)]
[Thread 0x7fffc667b700 (LWP 12740) exited]
[New Thread 0x7fffc667b700 (LWP 12741)]
[Thread 0x7fffc667b700 (LWP 12741) exited]
[New Thread 0x7fffc667b700 (LWP 12742)]
[New Thread 0x7fffaed0e700 (LWP 12743)]
[New Thread 0x7fffae50d700 (LWP 12744)]
[New Thread 0x7fffadd0c700 (LWP 12745)]
[Thread 0x7fffc667b700 (LWP 12742) exited]
[Thread 0x7fffadd0c700 (LWP 12745) exited]
[Thread 0x7fffaed0e700 (LWP 12743) exited]
[Thread 0x7fffc6e7c700 (LWP 12735) exited]
[New Thread 0x7fffadd0c700 (LWP 12747)]
Gtk-Message: GtkDialog mapped without a transient parent. This is discouraged.
[Thread 0x7fffadd0c700 (LWP 12747) exited]
[New Thread 0x7fffadd0c700 (LWP 12753)]
[New Thread 0x7fffc6e7c700 (LWP 12755)]
[New Thread 0x7fffaed0e700 (LWP 12756)]
[Thread 0x7fffadd0c700 (LWP 12753) exited]
[Thread 0x7fffaed0e700 (LWP 12756) exited]
[Thread 0x7fffae50d700 (LWP 12744) exited]

Thread 1 "shotwell" received signal SIGSEGV, Segmentation fault.
__strlen_avx2 () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:62
62	../sysdeps/x86_64/multiarch/strlen-avx2.S: No such file or directory.
(gdb) bt
#0  __strlen_avx2 () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:62
#1  0x00007ffff7331aee in g_utf8_collate_key_for_filename () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00005555556e3b10 in folders_sidebar_entry_construct (object_type=<optimised out>, dir=dir@entry=0x7fff9c28a760)
    at ./src/folders/FoldersBranch.vala:171
#3  0x00005555556e40d0 in folders_sidebar_entry_new (dir=0x7fff9c28a760) at ./src/folders/FoldersBranch.vala:169
#4  folders_branch_add_entry (self=0x555555eec090, media=<optimised out>) at ./src/folders/FoldersBranch.vala:100
#5  0x00005555556e45f1 in folders_branch_on_media_contents_altered (self=0x555555eec090, added=<optimised out>, removed=0x0)
    at ./src/folders/FoldersBranch.vala:59
#6  0x00007ffff75d8f9d in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#7  0x00007ffff75ebcde in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#8  0x00007ffff75f44b5 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#9  0x00007ffff75f4ecf in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#10 0x00005555557f6075 in media_source_collection_real_notify_contents_altered (base=<optimised out>, added=added@entry=0x555556520a60, 
    removed=removed@entry=0x0) at ./src/MediaDataRepresentation.vala:579
#11 0x0000555555750907 in library_photo_source_collection_real_notify_contents_altered (base=<optimised out>, added=0x555556520a60, removed=0x0)
    at ./src/Photo.vala:4619
#12 0x00005555556624b5 in data_collection_real_add_many (self=0x555555cfd0e0, objects=<optimised out>, monitor=0x0, monitor_target=0x0)
    at ./src/core/DataCollection.vala:351
#13 0x00005555557f492c in media_source_collection_real_import_many (self=0x555555cfd0e0, media=0x555556520d00)
    at ./src/MediaDataRepresentation.vala:647
#14 0x000055555575b3b2 in batch_import_flush_ready_sources (self=self@entry=0x5555562296d0) at ./src/BatchImport.vala:1207
#15 0x000055555575b777 in batch_import_report_completed (self=0x5555562296d0, 
    where=0x555555877f68 "completed preparing files, all outstanding imports completed") at ./src/BatchImport.vala:629
---Type <return> to continue, or q <return> to quit---
#16 0x000055555575ba35 in batch_import_display_imported_timer (self=0x5555562296d0) at ./src/BatchImport.vala:1293
#17 _batch_import_display_imported_timer_gsource_func (self=0x5555562296d0) at BatchImport.c:5382
#18 0x00007ffff73008a3 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007ffff72ffe25 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007ffff73001f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007ffff730027c in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#22 0x00007ffff78bdc4d in g_application_run () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#23 0x00005555557e3e0a in application_start (self=0x555555cc5460, argv=0x0, argv_length1=0) at ./src/Application.vala:182
#24 0x00005555556e6018 in library_exec (mounts=<optimised out>, mounts_length1=<optimised out>) at ./src/main.vala:198
#25 0x00005555556e6d88 in _vala_main (args=<optimised out>, args_length1=<optimised out>) at ./src/main.vala:441
#26 0x00005555555debe0 in main (argc=<optimised out>, argv=<optimised out>) at ./src/main.vala:330
