From MozillaZine Knowledge Base
Web pages (and web servers) can ask a browser to automatically refresh a page after a given timeout by including the HTML element
Automatic refreshes also have accessibility implications; sudden replacement of content can be disorienting. The UAAG recommends giving users the option to disable/ignore automatic page refreshes for this reason. This preference allows users to block automatic page refreshing, instead displaying a message allowing them to manually refresh the page.
Possible values and their effects
Instead of refreshing a page automatically when
Allow automatic page refreshes
A checkbox labeled “Warn me when web sites try to redirect or reload the page” is located under “Tools -> Options -> Advanced -> General -> Accessibility”.
First checked in
2007-02-08 by Asaf Romano (patch by Mark Pilgrim)
Has an effect in