https://developer.mozilla.org/en-US/docs/Web/API/WebGLRenderingContext/getAttachedShaders
WebGLRenderingContext: getAttachedShaders() method - Web APIs | MDN
The WebGLRenderingContext.getAttachedShaders() method of the WebGL API returns a list of WebGLShader objects attached to a WebGLProgram.
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