Extension "apps-menu" depends on port "x11/gnome-menus" which is not required.
I was just bitten by this. gnome-shell-extensions-3.18.4 has a hidden dependency on gnome-menus-3.13.3_1 through at least one shell extension. The one that triggered a missing TypeLib stacktrace for me was "Auto move windows". Pressing the gear button tries to load a menu which fails. Installing gnome-menus makes the error go away.
gnome-shell-extension requires gnome-menus package to be installed for "Applications menu" to work. FreeBSD 11.1-RELEASE #0 r321309: Fri Jul 21 02:08:28 UTC 2017 root@releng2.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC This issue was hard to debug. Finally found error in ~/.cache/gdm/session.log (gnome-shell:4332): Gjs-WARNING **: JS ERROR: Exception in callback for signal: extension-found: Error: Requiring GMenu, version none: Typelib file for name space 'GMenu' (any version) not found @/usr/local/share/gnome-shell/extensions/apps-menu@gnome-shell-extensions.gcampax.github.com/extension.js:4
ping!
Over to maintainer