Authenticated session
Cookie configured
Your CookieBank session now has the SameSite policy required by this mission.
Cross-site origin not configured.
SameSite labs require a second registrable site, not merely another subdomain. Set VITE_LAB_CROSS_SITE_ORIGIN to an HTTPS origin that routes to this app (for example a second domain you control).
Next step
Leave CookieBank and visit the external promotion site. Perform the action there and observe whether your CookieBank session accompanies the cross-site request.