Clicking on Searx as a non admin user doesn't redirect to search page.

I logged in as non-admin user in my freedombox instance. I tried to click on the frontpage shortcut of searx.

What I expected

searx search page https://localhost:4430/searx is displayed

What happened

But I stay in the front page and url changes to https://localhost:4430/plinth?next=https%3a%2f%2flocalhost%3a4430%2fsearx%2f.

Is it the expected behaviour?

Steps to reproduce

• Install searx as an admin user and keep it enabled
• Logout and login as non-admin user
• Try to click on front page shortcut for searx

EDIT: I am suspecting this might be because of sso.