src/vs/workbench/contrib/files/browser/views/explorerView.ts/ExplorerView/getOptimalWidth
class ExplorerView:	override getOptimalWidth(): number {
		const parentNode = this.tree.getHTMLElement();
		const childNodes = ([] as HTMLElement[]).slice.call(parentNode.querySelectorAll('.explorer-item .label-name')); // select all file labels

		return DOM.getLargestChildWidth(parentNode, childNodes);
	}