diff --git a/kitty/rgb.py b/kitty/rgb.py
index 5526ce563..614ab7f90 100644
--- a/kitty/rgb.py
+++ b/kitty/rgb.py
@@ -70,7 +70,7 @@ def to_color(raw: str, validate: bool = False) -> Optional[Color]:
         elif raw.startswith('rgb:'):
             val = parse_rgb(raw[4:])
     if val is None and validate:
-        raise ValueError(f'Invalid color name: {raw}')
+        raise ValueError(f'Invalid color name: {raw!r}')
     return val