I am trying to post 1 form with atlassian-connect-token. But where to place this token in my Thymeleaf page? As per documentation, I have added : in header but it is not working.
You are sending the token in the HTTP header Authorization when you submit the form? How are you doing that?
Both the alternative solutions described in this answer to the StackOverflow post How to set a Header field on POST a form? should work: including a hidden from element or a query string parameter, in both cases named jwt.