src/vs/editor/browser/viewParts/minimap/minimap.ts/InnerMinimap/_getBuffer
class InnerMinimap:	private _getBuffer(): ImageData | null {
		if (!this._buffers) {
			if (this._model.options.canvasInnerWidth > 0 && this._model.options.canvasInnerHeight > 0) {
				this._buffers = new MinimapBuffers(
					this._canvas.domNode.getContext('2d')!,
					this._model.options.canvasInnerWidth,
					this._model.options.canvasInnerHeight,
					this._model.options.backgroundColor
				);
			}
		}
		return this._buffers ? this._buffers.getBuffer() : null;
	}