diff --git a/lib/sup/colormap.rb b/lib/sup/colormap.rb
index 7de48db..087995a 100644
--- a/lib/sup/colormap.rb
+++ b/lib/sup/colormap.rb
@@ -175,6 +175,10 @@ class Colormap
     color
   end
 
+  def sym_is_defined sym
+      return sym if @entries.member? sym
+  end
+
   ## Try to use the user defined colors, in case of an error fall back
   ## to the default ones.
   def populate_colormap
diff --git a/lib/sup/modes/thread-index-mode.rb b/lib/sup/modes/thread-index-mode.rb
index 0c7a3f2..c90a42c 100644
--- a/lib/sup/modes/thread-index-mode.rb
+++ b/lib/sup/modes/thread-index-mode.rb
@@ -893,7 +893,7 @@ protected
       [:to_me_color, t.labels.member?(:attachment) ? "@" : " "],
       [:to_me_color, dp ? ">" : (p ? '+' : " ")],
     ] +
-      (t.labels - @hidden_labels).map { |label| [:label_color, "#{label} "] } +
+      (t.labels - @hidden_labels).map { |label| [Colormap.sym_is_defined("#{label}_color".to_sym) || :label_color, "#{label} "] } +
       [
       [subj_color, t.subj + (t.subj.empty? ? "" : " ")],
       [:snippet_color, t.snippet],