I did install the newest version of Home Assistant a couple days ago and discovered I could use ?kiosk after any dashboard and it would disable the top and side bar. Now I reinstalled Home Assistant on my target raspberry pi and while adding ?kiosk after a dashboard it doesnt go into kiosk mode anymore. Is there some setting that can fix this? I’ve tried accessing the same page with ?kiosk through different tablets and computer but it doesnt work.
Thank you so much for your help!
It works for me without any problems on the latest HA core-2025.11.3
I type it in as:
http://homeassistant.local:8123/lovelace/0?kiosk
That worked just before I did a reinstall of the system. Must be some setting.
I did a work around and install kiosk-mode from GitHub - NemesisRE/kiosk-mode: 🙈 Hides the Home Assistant header and/or sidebar
I fixes my problem by a different approach.
?kiosk parameter to enable kiosk mode is a kiosk-mode feature, it is not a Home Assistant feature, so it makes sense that it started to work when you installed kiosk-mode. Are you totally sure that you didn’t have kiosk-mode installed before? 
Glad you found a workaround with the integration!
If that ever breaks after a Home Assistant update (which happens sometimes with URL hacks) or if you want a simpler native solution, I built a free Android app called WebView Nova to solve this exact problem.
It forces “Immersive Mode” natively on the tablet, so you don’t need ?kiosk in the URL at all. It just displays the dashboard full-screen automatically.
Here is the link if you want to test it:
Just a note, kiosk.mode’s ?kiosk parameter does not put the dashboard in full-screen or enable immersive mode, it just hides the header and the sidebar of the dashboard.