First off, I want to say I have found and read through the unstable Scribus AppImage discussion thread, but...
1. This issue is different from the one described there; and
2. The solution mooted in that thread does not resolve my issue
My issue is that when I open the Scribus 1.5.3 AppImage, none of the menus have any items on them. The menu titles show, and when clicked they do produce physical menus, but those menus have no menu item contents. That is, even if one tries to click randomly on some part of the menu, nothing gets selected, and no functions are performed.
Moreover, the menu titles are crammed immediately next to each other, instead of having the usual spacing between them one might expect.
If one knows the keyboard shortcuts to specific menu item functions (like New, or Open, or Quit, etc.) that works. However, this problem basically cripples the program and makes it unusable.
Whether I just double-click the AppImage file itself, or try the "LD_PRELOAD=/usr/lib64/libxcb.so.1" prefix in a terminal window, the result is identical.
Separately, I can't figure out how to summon a menu editor function to manually add this program to the menu.