src/vs/workbench/contrib/notebook/browser/diff/notebookDiffOverviewRuler.ts/NotebookDiffOverviewRuler/_renderOverviewViewport
class NotebookDiffOverviewRuler:	private _renderOverviewViewport(): void {
		const layout = this._computeOverviewViewport();
		if (!layout) {
			this._overviewViewportDomElement.setTop(0);
			this._overviewViewportDomElement.setHeight(0);
		} else {
			this._overviewViewportDomElement.setTop(layout.top);
			this._overviewViewportDomElement.setHeight(layout.height);
		}
	}