We would like to have out Omeka S installation available at example.org but to be able to access our sites via site1.example.org, site2.example.org etc. as well as (or instead of) example.org/s/site1 and example.org/s/site2.
There are a couple of modules out there, but there may be more I am not aware of.
Both are third party modules, and one of them is on the Omeka S modules page. There was a problem reported with SiteSlugAsSubdomain two years ago, as validation for signing-in failed, but it looks like the solution is available on the GitHub repository even if a new release has not been made.
Before we invest time in either of these options, I was wondering if any other users here have different recommendations for this requirement?