diff --git a/rc.lua b/rc.lua
index f56391f..2026bcd 100644
--- a/rc.lua
+++ b/rc.lua
@@ -137,7 +137,7 @@ tyrannical.tags = {
         screen      = {1,2},
         layout      = awful.layout.suit.max,
         no_focus_stealing_in = true,
-        class = {"Firefox", "Iceweasel", "Chromium"},
+        class = {"Navigator", "Firefox", "Iceweasel", "Chromium"},
         exec_once   = {"firefox -P default"}
     },
     {
@@ -161,7 +161,7 @@ tyrannical.tags = {
         screen = screen.count()>1 and 2 or 1,
         layout = awful.layout.suit.max,
         no_focus_stealing_in = true,
-        class = {"Thunderbird", "Icedove"},
+        class = {"Mail", "Thunderbird", "Icedove"},
         exec_once   = {"thunderbird"},
     },
 }