Weird - this error is from SDL, not openxcom directly. Maybe the update broke that? Assuming you've checked you've got the latest version of sdl1.x installed as well (OpenXcom is oldschool so still uses sdl1.x, not 2 FYI)
I can't see anything in the openxcom code that would cause this - we don't ask for any weird attributes that can't be satisfied by any of the glx visuals listed in the glxinfo output....
It might be interesting to try to get an apitrace of openxcom failing to start - it should hopefully list the glx calls that sdl is trying to do, and which is failing. It may give us pointers on what's going on?
Thanks again for looking. So I took the nuclear option and re-installed all of the SDL-related packages by running 'sudo dnf reinstall SDL* -y', and here's what it re-installed:
Reinstalled:
SDL-1.2.15-33.fc29.x86_64 SDL-devel-1.2.15-33.fc29.x86_64
SDL-static-1.2.15-33.fc29.x86_64 SDL2-2.0.8-6.fc29.i686
SDL2-2.0.8-6.fc29.x86_64 SDL2-devel-2.0.8-6.fc29.x86_64
SDL2-static-2.0.8-6.fc29.x86_64 SDL2_gfx-1.0.3-3.fc29.x86_64
SDL2_gfx-devel-1.0.3-3.fc29.x86_64 SDL2_gfx-docs-1.0.3-3.fc29.noarch
SDL2_image-2.0.3-2.fc29.x86_64 SDL2_image-devel-2.0.3-2.fc29.x86_64
SDL2_mixer-2.0.2-5.fc29.x86_64 SDL2_mixer-devel-2.0.2-5.fc29.x86_64
SDL2_net-2.0.1-7.fc29.x86_64 SDL2_net-devel-2.0.1-7.fc29.x86_64
SDL2_ttf-2.0.14-7.fc29.x86_64 SDL2_ttf-devel-2.0.14-7.fc29.x86_64
SDL_Pango-0.1.2-27.fc29.x86_64 SDL_Pango-devel-0.1.2-27.fc29.x86_64
SDL_gfx-2.0.25-9.fc29.x86_64 SDL_gfx-devel-2.0.25-9.fc29.x86_64
SDL_image-1.2.12-20.fc29.x86_64 SDL_image-devel-1.2.12-20.fc29.x86_64
SDL_mixer-1.2.12-16.fc29.x86_64 SDL_mixer-devel-1.2.12-16.fc29.x86_64
SDL_mng-0.2.7-8.fc29.x86_64 SDL_mng-devel-0.2.7-8.fc29.x86_64
SDL_net-1.2.8-13.fc29.x86_64 SDL_net-devel-1.2.8-13.fc29.x86_64
SDL_sound-1.0.3-22.fc29.x86_64 SDL_sound-devel-1.0.3-22.fc29.x86_64
SDL_ttf-2.0.11-13.fc29.x86_64 SDL_ttf-devel-2.0.11-13.fc29.x86_64
Unfortunately, OpenXcom is still failing for me:
$ ./OpenXcom_20181103_d3affd504_x86-64.AppImage
zenity: /tmp/.mount_OpenXczJPfcu/lib/x86_64-linux-gnu/libdbus-1.so.3: no version information available (required by /lib64/libatk-bridge-2.0.so.0)
zenity: /tmp/.mount_OpenXczJPfcu/lib/x86_64-linux-gnu/libdbus-1.so.3: no version information available (required by /lib64/libatspi.so.0)
(zenity:2105): Gtk-WARNING **: 08:22:52.681: Could not find the icon 'dialog-error-ltr'. The 'hicolor' theme
was not found either, perhaps you need to install it.
You can get a copy from:
http://icon-theme.freedesktop.org/releases
(zenity:2105): Gtk-WARNING **: 08:22:52.681: Could not load a pixbuf from /org/gtk/libgtk/icons/48x48/status/image-missing.png.
This may indicate that pixbuf loaders or the mime database could not be found.
**
Gtk:ERROR:gtkiconhelper.c:494:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /org/gtk/libgtk/icons/48x48/status/image-missing.png: Unrecognized image file format (gdk-pixbuf-error-quark, 3)
OpenXcom has crashed: Couldn't find matching GLX visual
More details here: /home/jabels/.local/share/openxcom/openxcom.log
If this error was unexpected, please report it to the developers.
Aborted (core dumped)
I've not used apitrace before, but I'll snag it and see if I can figure it out.
--- posts merged. Come on people, it's not like I have nothing better to do! ---So... I fixed it.
Not sure WHAT was causing the problem, but after tiring of bashing my head against packages, dependencies and permissions, I re-created my directories under a new user account, copied over my game data, saves, config file and ran it... and it crashed again. So I deleted the ./config/openxcom/options.cfg file, and it launched! Only at default resolution, but that's easy enough to change. Now to figure out WHAT it was in my original config file that caused me a few days of heartache.
Attached is the busted options file that was causing the issue, and also the cleanly-made, working one from launching the game fresh.
Thanks for all y'alls tips and assistance. Glad in the end it was something simple.