Steps to Reproduce:
Use MediaWiki-extensions-GuidedTour on a wiki and open the JavaScript console.
Actual Results
In Firefox:
Cookie “mw-tour” will be soon rejected because it has the “sameSite” attribute set to “none” or an invalid value, without the “secure” attribute. To know more about the “sameSite“ attribute, read https://developer.mozilla.org/docs/Web/HTTP/Headers/Set-Cookie/SameSite
Expected Results
No warning in the JavaScript console.