Segfault in BG_RECENT_SOURCE
That's currently one of the most reported GNOME 3.34 issues on the Ubuntu error tracker (but there is no manual report/user description though)
Report from 3.34.0
#0 0x00007f8bec811731 in g_type_check_instance_cast () from /srv/daisy.ubuntu.com/production/cache/Ubuntu 19.10/cache-0Hbtmf/sandbox/Ubuntu 19.10/amd64/report-sandbox/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
No symbol table info available.
#1 0x000056307862e3b6 in BG_RECENT_SOURCE (ptr=0x56307a285820) at ../panels/background/bg-recent-source.h:29
No locals.
#2 enumerate_children_finished_cb (source=0x5630799ddb00, result=0x56307a1a5b10, user_data=user_data@entry=0x56307a285820) at ../panels/background/bg-recent-source.c:267
self = <optimized out>
enumerator = <optimized out>
error = 0x0
#3 0x00007f8bec8e9f89 in g_task_return_now (task=0x56307a1a5b10) at ../../../gio/gtask.c:1212
No locals.
#4 0x00007f8bec8e9fcd in complete_in_idle_cb (task=0x56307a1a5b10) at ../../../gio/gtask.c:1226
No locals.
#5 0x00007f8bec70172e in g_main_context_dispatch () from /srv/daisy.ubuntu.com/production/cache/Ubuntu 19.10/cache-0Hbtmf/sandbox/Ubuntu 19.10/amd64/report-sandbox/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#6 0x00007f8bec701ae0 in g_main_context_iterate.isra () from /srv/daisy.ubuntu.com/production/cache/Ubuntu 19.10/cache-0Hbtmf/sandbox/Ubuntu 19.10/amd64/report-sandbox/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#7 0x00007f8bec701b83 in g_main_context_iteration () from /srv/daisy.ubuntu.com/production/cache/Ubuntu 19.10/cache-0Hbtmf/sandbox/Ubuntu 19.10/amd64/report-sandbox/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#8 0x00007f8bec917a65 in g_application_run (application=0x563079fba3a0, argc=<optimized out>, argv=<optimized out>) at ../../../gio/gapplication.c:2559
arguments = 0x563079fbd060
status = 0
context = 0x5630797e2c70
acquired_context = 1
__FUNCTION__ = "g_application_run"
#9 0x00005630785f97b9 in main (argc=<optimized out>, argv=<optimized out>) at ../shell/main.c:70
application = 0x563079fba3a0