Window buttons not visible on window managers that do not draw window decorations

[ompjuter]

Descritpion:
The Awesome window manager on Linux does not draw the usual buttons on the title bar of windows, it does not even draw title bars.
This makes the Kiwix gui unusable, since several buttons are inaccessible.

Reproduction:

1. Install Awesome WM or some other WM that does not draw window title bars
   sudo apt install awesome
2. Switch to it in your desktop manager and login
3. Modkey (usually windows or alt) + return key to launch a terminal
4. Launch Kiwix by running the kiwix command
5. Observe that the buttons are missing

Expected behavior:
The buttons are visible and clickable.

Possible solutions:
Move the buttons from the title bar or
add keyboard shortcuts that can be used instead of the buttons.