Is there a way to make discourse send out a customized email to for example “users not active in the last 4 weeks” etc?
I think this is where the email digest comes in. By default the format is “A brief summary of [site name] since your last visit on [last visit date].” Your users may opt out of this though, and maybe it is just me but it seems like users get digests more often the more active they are, or simply fewer and fewer digests the longer they’re inactive.
It is the opposite, you only get digests if you are inactive. But weekly digests for inactive users is the default.
Note that inactive users will only be sent weekly digests for one year by default.