I am using the latest 2021.1.4 version of Home Assistant Core but the issue has been the same since I installed homeassistant. I always select ‘Yes’ when prompted if I want to stay logged in, but whenever I close the tab or the browser I am again prompted to login to home assistant. This problem is present on multiple browser (firefox, edge, chrome) and on windows and macos.
Same problem in Firefox. Tried refreshing/resetting Firefox, added exception, etc. Nothing works. It suck to have to re-login every time, even when I want to open it in a new tab, especially with dual authentication