--- a/mod_muc_inject_mentions/mod_muc_inject_mentions.lua	Sun Sep 20 14:57:55 2020 +0200
+++ b/mod_muc_inject_mentions/mod_muc_inject_mentions.lua	Sun Sep 20 15:04:22 2020 +0200
@@ -143,7 +143,9 @@
 
                 -- nickname: ...
                 elseif not has_preffix and has_suffix then
-                    if body:sub(first - 1, first - 1) == " " then
+                    if body:sub(first - 1, first - 1) == " " or
+                        body:sub(first - 1, first - 1) == "\n"
+                    then
                         table.insert(mentions, {bare_jid=bare_jid, first=first, last=last})
                     end
                 end