I want to add a message for example: If the user leaves the browser tab, the message "Looks like you're gone ..." should appear. When the user returns to the page, change the message to "Good to be back".
Is it possible to do something like this?
Crate an eventListener on your window, with the load event, and simply show an alert.
And create an event on your window called onbeforeunload (more info about the event), where you show an alert while leaving the page.
Note: onbeforeunload won't work in this snippet, but try putting inside your code.
window.addEventListener('load', (event) =>{
alert("Looks like you are back");
});
window.onbeforeunload = function() {
alert("Looks like you want to leave");
};You can achieve this with the Page Visibility API
Answered here