Module:If preview/configuration/doc

This is a documentation subpage for Module:If preview/configuration.
It may contain usage information, categories and other content that is not part of the original module page.

This Lua module is used in system messages, and on approximately 315,000 pages, or roughly 1% of all pages.
Changes to it can cause immediate changes to the Wikipedia user interface.
To avoid major disruption and server load, any changes should be tested in the module's /sandbox or /testcases subpages, or in your own module sandbox. The tested changes can be added to this page in a single edit. Please discuss changes on the talk page before implementing them.

This module does the actual work for determining if the page is in preview mode. It is a separate module so mw.loadData can only run it once per page, rather than once per use.