Enable my app to get embedded in an iframe

Got www.mysite.xx and want to have it shown in someone elses site www.theirsite.yy in an iframe. So on sprintr, for mysite.xx, on the production environement, in general settings, I have set the site to allow http headers: Now when I go to https://www.theirsite.yy it attempts to show the page, but keeps refreshing the iframe permanently. Looking in the console of the webbrowser I see repetative authorisation errors: What should I do to resolve those? Apparently it does work when the system on www.mysite.xx is rebooting:  
1 answers

You may need to set the custom settings “com.mendix.core.SameSiteCookies to None or Lax instead of Strict :