Issue #26736: Used HTTPS for external links in the documentation if possible.
diff --git a/Doc/howto/unicode.rst b/Doc/howto/unicode.rst
index 8776e3c..24051bf 100644
--- a/Doc/howto/unicode.rst
+++ b/Doc/howto/unicode.rst
@@ -214,7 +214,7 @@
origin and development of Unicode is also available on the site.
To help understand the standard, Jukka Korpela has written `an introductory
-guide <http://www.cs.tut.fi/~jkorpela/unicode/guide.html>`_ to reading the
+guide <https://www.cs.tut.fi/~jkorpela/unicode/guide.html>`_ to reading the
Unicode character tables.
Another `good introductory article <http://www.joelonsoftware.com/articles/Unicode.html>`_