Last tested: Feb 24, 2021
You can add
/embed/ in the URL of an explore, Look or dashboard. Both will make the content full screen and remove the top navigation bar. For dashboards next, you can add a parameter,
print_mode=true to the URL. (/dashboards-next/1234?print_mode=true)
There are subtle differences between the two, but it's most important to note that
/embed/ will show exactly the way that embed users will see the content.