src/vs/base/browser/ui/selectBox/selectBoxCustom.ts/SelectBoxList/onDownArrow
class SelectBoxList:	private onDownArrow(e: StandardKeyboardEvent): void {
		if (this.selected < this.options.length - 1) {
			dom.EventHelper.stop(e, true);

			// Skip disabled options
			const nextOptionDisabled = this.options[this.selected + 1].isDisabled;

			if (nextOptionDisabled && this.options.length > this.selected + 2) {
				this.selected += 2;
			} else if (nextOptionDisabled) {
				return;
			} else {
				this.selected++;
			}

			// Set focus/selection - only fire event when closing drop-down or on blur
			this.select(this.selected);
			this.selectList.setFocus([this.selected]);
			this.selectList.reveal(this.selectList.getFocus()[0]);
		}
	}