update to latest documentation and update copyright year
diff --git a/MagickCore/display.c b/MagickCore/display.c
index 62d02bf..8916fb0 100644
--- a/MagickCore/display.c
+++ b/MagickCore/display.c
@@ -17,7 +17,7 @@
% July 1992 %
% %
% %
-% Copyright 1999-2020 ImageMagick Studio LLC, a non-profit organization %
+% Copyright 1999-2021 ImageMagick Studio LLC, a non-profit organization %
% dedicated to making software imaging solutions freely available. %
% %
% You may not use this file except in compliance with the License. You may %
