src/vs/editor/contrib/peekView/browser/peekView.ts/PeekViewWidget/setMetaTitle
class PeekViewWidget:	setMetaTitle(value: string): void {
		if (this._metaHeading) {
			if (value) {
				this._metaHeading.innerText = value;
				dom.show(this._metaHeading);
			} else {
				dom.hide(this._metaHeading);
			}
		}
	}