The Server Name Identification (SNI) standard means that the hostname may not be encrypted if you're using TLS. Also, whether you're using SNI or not, the TCP and IP headers are never encrypted. (If they were, your packets would not be routable.)
https://stackoverflow.com/questions/187655/are-https-headers-encrypted#187679
Incorrect dukk. Firefox isn’t built on Chromium, Firefox predates google let alone Google chromium.