src/vs/base/browser/ui/button/button.ts/Button/label
class Button:	set label(value: string) {
		this._element.classList.add('monaco-text-button');
		if (this.options.supportIcons) {
			const content: HTMLSpanElement[] = [];
			for (let segment of renderLabelWithIcons(value)) {
				if (typeof (segment) === 'string') {
					segment = segment.trim();

					// Ignore empty segment
					if (segment === '') {
						continue;
					}

					// Convert string segments to <span> nodes
					const node = document.createElement('span');
					node.textContent = segment;
					content.push(node);
				} else {
					content.push(segment);
				}
			}

			reset(this._element, ...content);
		} else {
			this._element.textContent = value;
		}
		if (typeof this.options.title === 'string') {
			this._element.title = this.options.title;
		} else if (this.options.title) {
			this._element.title = value;
		}
	}