Replication of Replication

I have 3 servers running CentOS+PG 11 
(postgresql11-server-11.5-1PGDG.rhel7.x86_64):
- s1: main db + publication
- s2: subscription of the main db
all works fine until here...
Now, I tried to config this:
- s2: publication of the same db that was replicated from s1
- s3: subscription of the db from s2
When I did this, replication s1=>s2 stopped, and replication s2=>s3 
never worked.
Is this not possible?