But it should support at least more than one platform. And it's disputable what exactly one considers as a platform, or just a flavor of some platform.
As said, it depends on the definition of platform for this case. All I see is support of a bunch of flavors of one platform, namely POSIX, unixoids, or how you want to call it. Yes, they are different desktop-platforms, but the purpose of this software is still limited to one specific environment. Or to give a different perspective, nobody would call it cross-platform, just because it can run with Gnome and KDE, under X11 and Wayland.
And I'm curious how much adaption happens for each OS really. Are there specific changes for MacOS and BSD, outside of some paths for configurations?
The entire point of POSIX is that, if you only use what it defines, your program automatically becomes cross-platform, because it will run on several Unices, as well as other systems (like Haiku).
It's probably fair to say that an application with native Wayland and X11 support is multiplatform. I can understand somebody disputing that, but certainly Linux and MacOS are different platforms. They don't even share executable formats.
