diff --git a/launch.sh b/launch.sh
old mode 100755
new mode 100644
diff --git a/src/tabs.py b/src/tabs.py
index 36688a8c..a1944b9c 100644
--- a/src/tabs.py
+++ b/src/tabs.py
@@ -512,7 +512,6 @@ class MucTab(ChatTab):
         Re-assign color to the participants of the room
         """
         room = self.get_room()
-        i = 0
         compare_users = lambda x: x.last_talked
         users = list(room.users)
         # search our own user, to remove it from the room
@@ -520,10 +519,9 @@ class MucTab(ChatTab):
             if user.nick == room.own_nick:
                 users.remove(user)
         nb_color = len(theme.LIST_COLOR_NICKNAMES)
-        for user in sorted(users, key=compare_users, reverse=True):
+        for i, user in enumerate(sorted(users, key=compare_users, reverse=True)):
             user.color = theme.LIST_COLOR_NICKNAMES[i % nb_color]
-            i += 1
-        self.text_win.rebuild_everything(self.get_room())
+        self.text_win.rebuild_everything(self._room)
         self.text_win.refresh(self._room)
         self.input.refresh()
 
@@ -580,6 +578,8 @@ class MucTab(ChatTab):
         if not arg.strip():
             self.core.add_message_to_text_buffer(self.get_room(),
                                                  _("The subject of the room is: %s") % self.get_room().topic)
+            self.text_win.refresh(self.get_room())
+            self.input.refresh()
             return
         subject = arg
         muc.change_subject(self.core.xmpp, self.get_room().name, subject)
diff --git a/src/windows.py b/src/windows.py
index f10c0853..53cd0781 100644
--- a/src/windows.py
+++ b/src/windows.py
@@ -576,7 +576,12 @@ class TextWin(Win):
         while txt != '':
             (txt, cutted_txt) = cut_text(txt, self.width-offset-1)
             if first:
-                color = message.nick_color or message.user.color if message.user else None
+                if message.user:
+                    color = message.user.color
+                elif message.nick_color:
+                    color = message.nick_color
+                else:
+                    color = None
             else:
                 color = None
             if first:
diff --git a/src/xhtml.py b/src/xhtml.py
index f0c55978..fee5a118 100644
--- a/src/xhtml.py
+++ b/src/xhtml.py
@@ -82,7 +82,7 @@ def convert_links_to_plaintext(text):
                         parent.text += link_text
                 parent.remove(child)
             previous_child = child
-    return ET.tostring(xml.getroot())
+    return ET.tostring(xml.getroot(), encoding=str)
 
 def clean_text(string):
     """