Crash on start: g_action_group_exporter_dispatch_events assertion failure

OS: Ubuntu 23.04 (Lunar Lobster)

After compiling and running juci, setting the theme to dark and opening a project, I restarted juci after having realized I wasn't sure how to bring back the menu after pressing "Toggle Menu". Upon attempting to start juci, I got the following:

t20kdc@Trevize:/media/modus/External2/jucipp/build$ src/juci

(juci:11719): Gtk-WARNING **: 12:26:29.003: Theme parsing error: gtk.css:1649:16: '-gtk-icon-size' is not a valid property name

(juci:11719): Gtk-WARNING **: 12:26:29.003: Theme parsing error: gtk.css:1652:16: '-gtk-icon-size' is not a valid property name

(juci:11719): Gtk-WARNING **: 12:26:29.026: Theme parsing error: gtk.css:1649:16: '-gtk-icon-size' is not a valid property name

(juci:11719): Gtk-WARNING **: 12:26:29.026: Theme parsing error: gtk.css:1652:16: '-gtk-icon-size' is not a valid property name
**
GLib-GIO:ERROR:../../../gio/gactiongroupexporter.c:167:g_action_group_exporter_dispatch_events: assertion failed: (((events & (ACTION_ENABLED_CHANGED_EVENT | ACTION_STATE_CHANGED_EVENT)) == 0) != ((events & (ACTION_REMOVED_EVENT | ACTION_ADDED_EVENT)) == 0))
Bail out! GLib-GIO:ERROR:../../../gio/gactiongroupexporter.c:167:g_action_group_exporter_dispatch_events: assertion failed: (((events & (ACTION_ENABLED_CHANGED_EVENT | ACTION_STATE_CHANGED_EVENT)) == 0) != ((events & (ACTION_REMOVED_EVENT | ACTION_ADDED_EVENT)) == 0))
Aborted (core dumped)

The traceback is as follows:

GLib-GIO:ERROR:../../../gio/gactiongroupexporter.c:167:g_action_group_exporter_dispatch_events: assertion failed: (((events & (ACTION_ENABLED_CHANGED_EVENT | ACTION_STATE_CHANGED_EVENT)) == 0) != ((events & (ACTION_REMOVED_EVENT | ACTION_ADDED_EVENT)) == 0))
Bail out! GLib-GIO:ERROR:../../../gio/gactiongroupexporter.c:167:g_action_group_exporter_dispatch_events: assertion failed: (((events & (ACTION_ENABLED_CHANGED_EVENT | ACTION_STATE_CHANGED_EVENT)) == 0) != ((events & (ACTION_REMOVED_EVENT | ACTION_ADDED_EVENT)) == 0))

Thread 1 "juci" received signal SIGABRT, Aborted.
__pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimised out>) at ./nptl/pthread_kill.c:44
Download failed: Invalid argument.  Continuing without source file ./nptl/./nptl/pthread_kill.c.                                                                                                                                            
44      ./nptl/pthread_kill.c: No such file or directory.
(gdb) bt
#0  __pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimised out>) at ./nptl/pthread_kill.c:44
#1  __pthread_kill_internal (signo=6, threadid=<optimised out>) at ./nptl/pthread_kill.c:78
#2  __GI___pthread_kill (threadid=<optimised out>, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
#3  0x00007ffff323c3b6 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#4  0x00007ffff322287c in __GI_abort () at ./stdlib/abort.c:79
#5  0x00007ffff6cc7d1e in g_assertion_message
    (domain=domain@entry=0x7ffff3572064 "GLib-GIO", file=file@entry=0x7ffff3594108 "../../../gio/gactiongroupexporter.c", line=line@entry=167, func=func@entry=0x7ffff3595e60 <__func__.5.lto_priv.58> "g_action_group_exporter_dispatch_events", message=message@entry=0x5555564909a0 "assertion failed: (((events & (ACTION_ENABLED_CHANGED_EVENT | ACTION_STATE_CHANGED_EVENT)) == 0) != ((events & (ACTION_REMOVED_EVENT | ACTION_ADDED_EVENT)) == 0))")
    at ../../../glib/gtestutils.c:3450
#6  0x00007ffff6d2f29e in g_assertion_message_expr
    (domain=domain@entry=0x7ffff3572064 "GLib-GIO", file=file@entry=0x7ffff3594108 "../../../gio/gactiongroupexporter.c", line=line@entry=167, func=func@entry=0x7ffff3595e60 <__func__.5.lto_priv.58> "g_action_group_exporter_dispatch_events", expr=expr@entry=0x7ffff3594ac8 "((events & (ACTION_ENABLED_CHANGED_EVENT | ACTION_STATE_CHANGED_EVENT)) == 0) != ((events & (ACTION_REMOVED_EVENT | ACTION_ADDED_EVENT)) == 0)") at ../../../glib/gtestutils.c:3476
#7  0x00007ffff350ab96 in g_action_group_exporter_dispatch_events (user_data=0x555555cd3410) at ../../../gio/gactiongroupexporter.c:167
#8  0x00007ffff6d033df in g_main_dispatch (context=0x555555ac1d30) at ../../../glib/gmain.c:3460
#9  g_main_context_dispatch (context=0x555555ac1d30) at ../../../glib/gmain.c:4200
#10 0x00007ffff6d5e2f8 in g_main_context_iterate.constprop.0 (context=0x555555ac1d30, block=<optimised out>, dispatch=1, self=<optimised out>) at ../../../glib/gmain.c:4276
#11 0x00007ffff6d02220 in g_main_context_iteration (context=context@entry=0x555555ac1d30, may_block=may_block@entry=1) at ../../../glib/gmain.c:4343
#12 0x00007ffff350cbfd in g_application_run (application=0x555555aae6e0, argc=<optimised out>, argv=0x7fffffffd898) at ../../../gio/gapplication.c:2573
#13 0x00005555556342fe in main ()
(gdb) 

In addition to this: I am unsure if this is or is not related, but there are two copies of the upper menu bar visible.