I downloaded the demo from itch.io, and tried to run it. I get a logo screen with options "play / settings / exit". When I select "play", I'm asked to select a mod. When I select "vanilla", the game immediately crashes.
Running in a terminal allows me to see messages like this (there are a lot of messages, but I've just picked a couple of bits that sound relevant):
[SNAKE2D] ---Running on a: Linux, amd64 Platform.
[SNAKE2D] SHADER COMPILED: class snake2d.VboSpritePointsOpti$ShaderDebug 1
[LWJGL] OpenGL debug message
ID: 0x502
Source: API
Type: ERROR
Severity: HIGH
Message: GL_INVALID_OPERATION error generated. VAO names must be generated with glGenVertexArrays before they can be bound or used.