quick mention should allow trailing .

fun.go

@@ -374,7 +374,7 @@ func memetize(honk *Honk) {
 	honk.Noise = re_memes.ReplaceAllStringFunc(honk.Noise, repl)
 }
 
-var re_quickmention = regexp.MustCompile("(^|[ \n])@[[:alnum:]]+([ \n]|$)")
+var re_quickmention = regexp.MustCompile("(^|[ \n])@[[:alnum:]]+([ \n.]|$)")
 
 func quickrename(s string, userid int64) string {
 	nonstop := true
@@ -389,7 +389,7 @@ func quickrename(s string, userid int64) string {
 			prefix += "@"
 			m = m[1:]
 			tail := ""
-			if m[len(m)-1] == ' ' || m[len(m)-1] == '\n' {
+			if last := m[len(m)-1]; last == ' ' || last == '\n' || last == '.' {
 				tail = m[len(m)-1:]
 				m = m[:len(m)-1]
 			}