https://myapps.motorolasolutions.com/msi-global-styles/21.17.1/handleFirstTab.js

1// eslint-disable-next-line func-names
2(function() {
3	function handleFirstTab(e) {
4		if (e.keyCode === 9) {
5			document.body.classList.add('user-is-tabbing');
6
7			window.removeEventListener('keydown', handleFirstTab);
8			window.addEventListener(
9				'mousedown',
10				// eslint-disable-next-line func-names
11				function() {
12					document.body.classList.remove('user-is-tabbing');
13					window.addEventListener('keydown', handleFirstTab);
14				},
15				{ once: true },
16			);
17		}
18	}
19
20	window.addEventListener('keydown', handleFirstTab);
21})();