This plugin works in combination with Greasemonkey userscripts that embed buttons into third party pages. Upon pressing the button some contacts gets saved here - so you can make all sorts of other notes back on your home server.
More specifically the project ships some userscripts that will look for chat mails to have them saved in a home server archive. Other userscripts will allow to retrieve some of those old mails and to show them on the third party server where it is active.
Get a source snapshot from one of the tags at Bitbucket: https://bitbucket.org/guidod/trac-userscriptservernotes-plugin/downloads/
Prebuilt RPMs are available from the Open Build Service: https://build.opensuse.org/package/show?project=home:guidod:tools:scm&package=trac-userscriptservernotes-plugin