SDL_Init( ... ) errors with: No available video device

[chickenSandwich]

This is occurring only with 2.0.15:

About

Memory: 15.5 GiB
Processor: Intel® Core™ i7-5960X CPU @ 3.00GHz × 16
Graphics: NVIDIA Corporation TU116 [GeForce GTX 1660 Ti]
OS Name: Pop!_OS 20.04 LTS
OS Type: 64-bit
GNOME Version: 3.36.8
Windowing System: X11

#include "SDL.h"

int main(int argc, char* argv[])
{
    if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_AUDIO) != 0) {
        SDL_Log("Unable to initialize SDL: %s", SDL_GetError());
        return 1;
    }

    /* ... */

    SDL_Quit();

    return 0;
}

Regardless of which value(s) I pass in to SDL_Init (SDL_INIT_VIDEO, or SDL_INIT_EVERYTHING)

When I was using SDL v2.0.10 everything was fine, but when I "upgrade" to 2.0.15 it started to error: No available video device.

I'm happy to provide any additional information.

[chickenSandwich]

I'm sorry, I didn't realize that I also need to install the X11 development libraries:

sudo apt install libx11-dev
sudo apt install libxext-dev