Add this to your application.yml
server:
servlet:
session:
cookie:
domain: olavgg.com
http-only: true
path: /
secure: true
This should work with Grails 4+ and I have verified that it works with Grails 5
For older Spring versions and Grails 3 this was
server:
session:
cookie:
domain: adminpanel-test-boost.ai
http-only: true
path: /
secure: true