The following section of the developer manual:

https://doc.sagemath.org/html/en/developer/sage_manuals.html

contains multiple reference to a dead link:

http://sphinx.pocoo.org

Component: documentation

Keywords: hyperlinks

Author: David Ayotte

Branch/Commit: bdc07ac

Reviewer: Kwankyu Lee

Issue created by migration from https://trac.sagemath.org/ticket/34740