+Remote mentions are delivered using the OStatus protocol.
+This protocol is used by Friendica and GNU Social and several other systems like Mastodon, but is not currently implemented in Diaspora.
+As the OStatus protocol allows this Friendica user can be @-mentioned by users from platforms using this protocol in conversations if the "Enable OStatus support" is activated on the Friendica node.
+These @-mentions wont be blocked, even if there is no relationship between the sender and the receiver of the message.
+
+Friendica makes no distinction between people and forums for the purpose of tagging.
+You can use @-mentions for forums like for other accounts to tag the forum.
+If you want to post something exclusively to a forum (e.g. the support forum) please use the bang-notation instead of the @tag.
+So !helpers will be an exclusive posting to the support forum if you are connected with the forum.
+If you select a forum from the ACL a !-mention will be added automatically to your posting.