Method _handleArrowNavigation

packages/main/src/MultiComboBox.ts:1306–1330

(e: KeyboardEvent, isDownControl: boolean)

	}

	_handleArrowNavigation(e: KeyboardEvent, isDownControl: boolean) {
		const isArrowDown = isDownControl || isDown(e);
		const hasSuggestions = this._getItems().length;

		e.preventDefault();

		if (this.hasValueStateMessage && !this.valueStateHeader) {
			this._setValueStateHeader();
		}

		if (isArrowDown && this.open) {
			if (this.showSelectAll) {
				(this._getResponsivePopover().querySelector(".ui5-mcb-select-all-checkbox") as CheckBox).focus();
				return;
			}
		}

		if (isArrowDown && hasSuggestions) {
			this._handleArrowDown();
		}

		if (!isArrowDown && !this.open && !this.readonly) {
			this._navigateToPrevItem();
		}
	}

	async _handleArrowDown() {
		const firstListItem = this.list?.getSlottedNodes<IMultiComboBoxItem>("items")[0];