Describe the bug
I am unable to use keyboard short cuts, for example in the PDF reader, unless I first click in the minibuffer first. This appears to be a recurrence of #657 and #237 (where I initially had fixed this with Xpra). wmctrl -m outputs

Name: Fluxbox
Class: N/A
PID: N/A
Window manager's "showing the desktop" mode: N/A

I have added it to the eaf-wm-focus-fix-wms option:

'("i3" "LG3D" "Xpra" "EXWM" "Xfwm4" "Fluxbox")

The problem persists despite this addition.

To Reproduce
I have the latest git copy of EAF and open up a random PDF. I press random keyboard shortcuts, such as i for inverting the color.

Expected behavior
It would respond to keyboard shortcuts.

Versions (please complete the following info):

• Distro and DE/WM: Turnkey Linux 16.1 and Fluxbox
• Versions of Dependencies:
  python3-pyqt5: 5.11.3+dfsg-1+b3
  python3-dbus: 1.2.8-3
  python3-pyqt5.qtwebengine: 5.11.3+dfsg-1+b3
• M-x emacs-version: GNU Emacs 29.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.5, cairo version 1.16.0) of 2022-01-26

Error logs
Please check the *eaf* buffer, if there is any error in it, paste it here.

QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-mymailuser'
Traceback (most recent call last):
  File "/home/mymailuser/emacs/emacs-application-framework/core/utils.py", line 61, in on_signal_received
    self._func(obj, *args, **kwargs)
  File "/home/mymailuser/emacs/emacs-application-framework/eaf.py", line 357, in eval_function
    buffer.eval_function(function_name)
  File "/home/mymailuser/emacs/emacs-application-framework/core/buffer.py", line 322, in eval_function
    getattr(self, function_name)()
  File "/home/mymailuser/emacs/emacs-application-framework/core/buffer.py", line 186, in move_cursor_to_corner
    QCursor().setPos(screen, screen.size().width(), screen.size().height())
TypeError: arguments did not match any overloaded call:
  setPos(int, int): argument 1 has unexpected type 'QScreen'
  setPos(QPoint): argument 1 has unexpected type 'QScreen'

Screenshots
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Additional context
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