I like Slack and similar having their own icon and entry in the alt-tab switcher. Absent ubiquitous PWA support, electron is sort of the least bad alternative.
ironically, windows just included this for Edge, you can alt tab between browser windows and you can put websites as taskbar apps ( and will also jump to all windows of the app easily as well)
You have to design your site for this, back in the IE days we did this for some corporate tools and went full kiosk mode. The user didn't even know that it was a website.