First thing I want to say is that I followed all of the suggestions in the OP (@oberon) that pertained to the problems I am experiencing since updating to the latest system upgrade. Also, I tried various solutions, provided by community users in this thread, to those problems. None of them worked to a fix.
All of the following occurred after a system upgrade to my now classic, and no longer supported, Manjarobox (Openbox) install.
Oblogout-manjaro no longer works. Super+X results in oblogout-manjaro failing to launch. Using the "oblogout" command in the terminal returns: "pyGTK missing, install python-gtk2". I rebuilt/reinstalled pygtk a couple of times and got the same results. And there is no "python-gtk2" located in the Manjaro or AUR repos.
In order to restart, I have to use the "reboot" command in the terminal. To logout of a session, I have to use the "fluxboxexit logout" command in the terminal. Surprisingly, though, i3lock does continue to work.
Icons. Like many others, the vast majority of my icons no longer work. All icons have defaulted to the standard GNOME icons that every Linux user on planet Earth is familiar with. I rebuilt/reinstalled LXAppearance / LXAppearance-obconf/ LXAppearance-GTK3/ LXAppearance-obconf-GTK3 multiple times to no avail. Also, to no avail, librsvg and qt5-svg were rebuilt/reinstalled multiple times.
Issuing the "pacman -Qo /usr/lib/python3.5/site-packages" terminal command returns: "error: No package owns /usr/lib/python3.5/site-packages". However, found inside the /usr/lib/python3.5/site-packages directory is a LightDM directory. I have rebuilt/reinstalled lightdm-gtk-greeter/ lightdm-gtk-greeter-settings but the directory still remains; not sure that is a problem, anyway.
I have an issue with an AUR package called "Cadence". Cadence, along with alsa-tools and jack, is audio software that allows me to use my professional RME sound card instead of my PC's built-in sound card. No two ways about it, Cadence is necessary because RME does not make drivers for Linux. With this latest system update, Cadence crashes on launch. Attempting to launch it from the terminal returns:
"Traceback (most recent call last):
File "/usr/share/cadence/src/cadence.py", line 24, in
from PyQt4.QtGui import QApplication, QDialogButtonBox, QLabel, QMainWindow, QSizePolicy
ImportError: /usr/lib/libharfbuzz.so.0: undefined symbol: FT_Get_Var_Blend_Coordinates".
The fix for Cadence failing to launch has been to downgrade the latest harfbuzz/ harfbuzz-icu packages to the previous version. Rebuilding/reinstalling the latest harfbuzz/ harfbuzz-icu packages does not result in a fix. Setting my pacman.conf to ignore harfbuzz/ harfbuzz-icu, at the moment.
I don't use Terminus nor Infinality fonts/bundles.
Additional FYI: errors in dmesg. Booting into Linux44 displays this error: "[ 8.797050] systemd: Failed to start Load Kernel Modules.
[ 8.797420] systemd: systemd-modules-load.service: Unit entered failed state.
[ 8.797429] systemd: systemd-modules-load.service: Failed with result 'exit-code'." I don't know what that means, but I was able to boot using the Linux44 kernel.
Booting into Linux49, dmesg displays these errors: "[ 0.153609] ACPI BIOS Error (bug): _SB.PCI0.USB0._PSW: Object (Integer) must be a control method with 1 arguments (20160831/nsarguments-147)
[ 0.153693] ACPI BIOS Error (bug): _SB.PCI0.USB1._PSW: Object (Integer) must be a control method with 1 arguments (20160831/nsarguments-147)
[ 0.153772] ACPI BIOS Error (bug): _SB.PCI0.USB2._PSW: Object (Integer) must be a control method with 1 arguments (20160831/nsarguments-147)". Again, I don't know what problems may arise from that.
This has been the first Manjaro system upgrade where I have experienced mega breakage of fundamental system functions and software tools. And I'm writing this in the 12th hour since I've been trying to fix things. Nothing that I have tried, in that time, has worked.