After backing up and deleting ~/.cache/rhythmbox and ~/.local/share/rhythmbox, then changing the location of my music library to a directory that doesn't exist, then restarting RB I can still get RB to crash when the CoverArt plugins are enabled, after a lot of random mousing around and clicking the CoverArt source however. Nothing in particular is printed to the console on the crash and I can't seem to make it crash when the plugins are disabled with an empty library.

Backtraces looks like this:

#0  0x00007ffff3118952 in ?? () from /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#1  0x00007ffff314517e in gdk_x11_window_get_xid () from /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#2  0x00007fffd00a23b8 in ?? () from /usr/lib/x86_64-linux-gnu/gtk-3.0/3.0.0/immodules/im-xim.so
#3  0x00007ffff3728b33 in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#4  0x00007ffff03c3adc in ffi_call_unix64 () from /usr/lib/x86_64-linux-gnu/libffi.so.6
#5  0x00007ffff03c340c in ffi_call () from /usr/lib/x86_64-linux-gnu/libffi.so.6
#6  0x00007ffff2315cd9 in g_callable_info_invoke () from /usr/lib/libgirepository-1.0.so.1
#7  0x00007ffff2317017 in g_function_info_invoke () from /usr/lib/libgirepository-1.0.so.1
#8  0x00007fffc7cdfbef in ?? () from /usr/lib/python3/dist-packages/gi/_gi.cpython-34m-x86_64-linux-gnu.so
#9  0x00007fffc7cd57ae in ?? () from /usr/lib/python3/dist-packages/gi/_gi.cpython-34m-x86_64-linux-gnu.so
#10 0x00007fffcc33a748 in PyObject_Call () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#11 0x00007fffcc404c59 in PyEval_EvalFrameEx () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#12 0x00007fffcc41a7c6 in PyEval_EvalCodeEx () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#13 0x00007fffcc41adf6 in ?? () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#14 0x00007fffcc33a748 in PyObject_Call () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#15 0x00007fffcc3323ed in ?? () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#16 0x00007fffcc33a748 in PyObject_Call () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#17 0x00007fffcc39ffa7 in PyEval_CallObjectWithKeywords () from /usr/lib/x86_64-linux-gnu/libpython3.4m.so.1.0
#18 0x00007fffc7cdf0e8 in ?? () from /usr/lib/python3/dist-packages/gi/_gi.cpython-34m-x86_64-linux-gnu.so
#19 0x00007ffff75263b8 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#20 0x00007ffff7537d3d in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#21 0x00007ffff753f6f9 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#22 0x00007ffff753fce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
---Type <return> to continue, or q <return> to quit---
#23 0x00007ffff386c5a4 in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#24 0x00007ffff388996b in gtk_window_propagate_key_event () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#25 0x00007ffff388c5bb in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#26 0x00007ffff374397c in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#27 0x00007ffff75263b8 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#28 0x00007ffff7537afb in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#29 0x00007ffff753f6f9 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#30 0x00007ffff753fce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#31 0x00007ffff386c5a4 in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#32 0x00007ffff3741edf in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#33 0x00007ffff374364a in gtk_main_do_event () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#34 0x00007ffff3133b72 in ?? () from /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#35 0x00007ffff725be24 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#36 0x00007ffff725c068 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#37 0x00007ffff725c10c in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#38 0x00007ffff189ea1c in g_application_run () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#39 0x00007ffff7ad8332 in rb_application_run (app=0x61d140, argc=argc@entry=1, argv=argv@entry=0x7fffffffe458)
    at rb-application.c:659
#40 0x0000000000400d22 in main (argc=1, argv=0x7fffffffe458) at main.c:95