This is frustrating because the unnamed people advising that were wrong. It confuses trapping page focus in a modal to blocking users from using the rest of their browser. Also, ugh APG.
css-tricks.com/there-is-no-nee…
If you find someone advising it, be wary of their UI / accessibility chops.
There is No Need to Trap Focus on a Dialog Element | CSS-Tricks
Accessibility advice around modals have commonly taught us to trap focus within the modal. Upon further research, it seems like we no longer need to trap focus within the (even in modal mode).Zell Liew (CSS-Tricks)