Thank you. Well, since I only have Linux on a virtual machine right now, things are hard for me to test. All I can do is see if stuff compiles and, that's it. Running a Windows build in WINE, eh? Yeah, I guess that's always an option, though I'm not sure if this could cause speed issues.
No speed issues with WINE; it’s not an emulator, just a (partial) replacement for OS functions. The problems are always about compatibility. It runs demanding games like Witcher 3 just fine, as well as Windows builds of most Unity/Unreal/Godot games.
I find it convenient to develop in Linux and test mostly in WINE - however, it’s more forgiving than real Windows so it is necessary to test on Windows occasionally.
SDL? If it works in Windows it should work in WINE. It’s more of a problem making portable Linux binaries because SDL has tons of dependencies, especially audio. Disabling SDL’s audio and using Miniaudio instead would probably solve 90% of those… although Linux core libs (glibc etc) cause so many backward/forward compat problems that WINE is (almost) preferable.