I don’t use a standard Desktop Environment for my GNU/Linux computers. Instead, I opt for a more minimal Window Manager, like Fluxbox (my Slackware default), StumpWM (my LISP based, hackable, preference), or Joe’s Window Manager (Better for laptops and non-LISP machines). I’m writing this post from JWM, in fact.
One problem I’ve run into with certain games is caused by the fact that these more minimal WMs often do not set a Primary Display by default. Seeing as the most common setup is one monitor, and there is a fallback to use the only existing monitor in X, and those who have more than one have probably explicitly set their monitors how they like them, it makes sense they might avoid declaring the only monitor as primary. And under most use cases, this doesn’t cause any problems.
But, well, if You use PulseAudio and try to run any Game Maker games in one of these WMs, You might find the following error showing up shortly after You launch the game, and shortly before it crashes:
[/etc/pulse/client.conf:26] Unknown lvalue 'allow-autospawn-for-root' in section 'n/a'. ~/.local/share/Steam/steamapps/common/<GAME FOLDER>/run.sh: line 3: 4320 Floating point exception
Running the following command sets my laptop’s only display to Primary:
xrandr --output LVDS1 --primary
And afterwards, I can launch the game without issue.