Limiting who can be mentioned?

[Jagster (Jakke Flemming)]

This topic is basically same as this:

Restrict who you can PM based on Groups

Hi Discourse Community! We’re using groups and categories to restrict what users can see/which forums they can participate in. This is mostly for privacy reasons/so that people aren’t inundated with topics that do not apply to them. However, we’ve noticed that when you @mention people, or when you private message them, you can actually tag (or reach out to) any user on the platform. With the @mention, you get a warning saying that you’re mentioning someone who doesn’t have access, which is sup…

a solution to limit PM, not for mentions per se

Discourse Restrict PMs to certain Groups