It turns out that some software will not render properly if the DPI is
not set using increments of 25% (i.e. 96, 120, 144, 168, 192, etc.).
Since GNOME and Plasma already use a scale factor of 2x, it makes sense
to use 2x for .Xresources as well. Now GTK and Qt applications should
share the same size across both bspwm and their respective DEs.
It turns out that placing similar config files (i.e. bspwm-related) in
the same directory is not the way to go about handling dotfiles since
each config file (or dotfile) *should* manipulate only a single program.
This was not the case back when I used urxvt (which would require the
old method of .Xresources), but now that I understand more about how
*modern* dotfiles work (with $XDG_CONFIG_HOME), separating dotfiles by
program became the obvious choice.
As much as I enjoyed using Waterfox, the update to Firefox (and its
developer tools) is pretty nice. Since many add-ons now support this
new version of Firefox, I think it's now time to make the switch.