diff --git a/hgext/color.py b/hgext/color.py
--- a/hgext/color.py
+++ b/hgext/color.py
@@ -11,7 +11,7 @@ This extension modifies the status and r
 to their output to reflect file status, the qseries command to add
 color to reflect patch status (applied, unapplied, missing), and to
 diff-related commands to highlight additions, removals, diff headers,
-and trailing whitespace.
+tabs, and trailing whitespace.
 
 Other effects in addition to color, like bold and underlined text, are
 also available. By default, the terminfo database is used to find the
@@ -61,6 +61,7 @@ effects may be overridden from your conf
   diff.deleted = red
   diff.inserted = green
   diff.changed = white
+  diff.tab =
   diff.trailingwhitespace = bold red_background
 
   # Blank so it inherits the style of the surrounding label
@@ -279,6 +280,7 @@ except ImportError:
            'diff.file_b': 'green bold',
            'diff.hunk': 'magenta',
            'diff.inserted': 'green',
+           'diff.tab': '',
            'diff.trailingwhitespace': 'bold red_background',
            'changeset.public' : '',
            'changeset.draft' : '',