Edit: Found out that Qwant Lite is the add on you want to use if you just want normal search engine behaviour. Not sure of the point of this non-lite version, but there we are.

There's a bug when you search from anywhere but Qwant home: it shows the results only temporarily before redirecting to https://lite.qwant.com/.

Pretty annoying. Hopefully they fix it as won't use it with this behaviour.