This thread is resolved. Here is a description of the problem and solution.
Problem: I have opted to enable auto login/logout but when I change languages, I have to login again.
Solution: It looks like this issue is actually happening due to settings with your hosting provider. Some hosting providers are adding this header to their request responses to protect against clickjacking attacks: X-Frame-Options: SAMEORIGIN
You can see this happening when you try to change languages in the browser console. See attached image.
You can try adding the following: X-Frame-Options "ALLOW-FROM http://it.domain.host,http://domain.host,http://fr.domain.host"
In addition, I would like to add that the "ALLOW-FROM" directive is not compatible with all browsers (eg. Chrome). https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options#Browser_compatibility https://www.owasp.org/index.php/Clickjacking_Defense_Cheat_Sheet#Browser_Support
A possible solution to include a fix for all the browsers is to use also the "Content Security Policy "frame-ancestors" directive" https://www.owasp.org/index.php/Content_Security_Policy_Cheat_Sheet#Preventing_Clickjacking
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