Not sure if this a documentation issue or something wrong on my system, but the alias types described here:
https://docs.opnsense.org/manual/aliases.html
(including screenshots how aliases look like, i.e. Host(s)) do not match whyt I see in 19.7
For every type (except for advanced which isnt really documented) and "URL Tables") there is just a "Content" field. It also doesn't seem to work. I.e. if a put a DNS name into "content" it won't be resolved and used in rules, if I use an external network list into "content" of a "URL Table" alias it won't be fetched and used.
I have the same issue i dont see the "hosts" field when using IP List.