Short URLs
I. Application name
Moved to Deploy XWiki as the Root Web Application.
Deploying as ROOT
Moved to Deploy XWiki as the Root Web Application.
When using the XWiki Debian Package
The Debian packages have their own root-webapp procedure: see Installation using Debian/Ubuntu (.DEB) packages.
II. Servlet mapping name
Moved to Short URLs, which explains why this part cannot be removed by configuration alone and which paths the rewriting must leave alone.
UrlRewriteFilter
Moved to Configure Short URLs with the UrlRewriteFilter.
Apache
Moved to Configure Short URLs with Apache HTTP Server.
Nginx
Moved to Configure Short URLs with Nginx.
III. action name
Moved to Hide the View Action in URLs.
IV. Error Page
Removed, not moved. The <error-page> element this section patched is no longer declared in the shipped web.xml, so the change it described no longer applies. For error pages in general, see Error Pages.
V. Conclusion
Moved to Short URLs, whose "What you end up with" section lists the resulting URLs.
Other solutions
Moved to Short URLs, which links the unverified Lighttpd + Jetty community draft under Related pages.