currently I have implemented the Cookie-Banner on the parent frame. However, it is also necessary to pass on the cookie values to the implemented iframe (different domain name). Each, the iframe and parent frame have a separate GTM-container. Is there any way to access the parent frame - cookie values via the iframe-GTM-container?
I have already tried it with post.Message. However, this only works when sending data from the iframe to the parent frame. However, not vice versa.