Wikipedia:Beware hidehack edits

Beware hidehack edits (or Bigfooting), hack edits which hide information inside tags or template parameters. Hidehack edits are not direct vandalism because they do not affect the displayed page, but merely conceal text which can be read by other users during an edit. Hidehacking is often used to spam opinion text, again, inside of pages, where it can be read during edits. The term "Bigfooting" refers to a hack edit made in March 2012 to mention "Bigfoot" inside a noinclude tag of an unprotected template.

Types of hidehack edits
A common form of hidehack edit will set a nonvalid parameter name inside a template, such as inside the top infobox. For example, someone might insert, "|nickname=The government of Xxx is a fascist regime" where the parameter "nickname=" is ignored (not displayed in the formatted page) and often allowed to remain inside the page. Another tactic is to put text into a closing "noinclude" tag (such as "&lt;/noinclude This is spam&gt;") where the text will be ignored, and other editors will get no warning of the spam text concealed after a hidehack edit.

Bigfooting
The term "Bigfooting" refers to a hack edit made by an IP address user, on 12 March 2012, to log an extended comment about "Bigfoot" inside an unprotected subtemplate of Template:Convert. That subtemplate, Template:Convert/-/AonSoff was reverted two hours later (see: dif946) and then full-protected to prevent any further hidehack edits. Apparently, some editors think that concealing text about controversial topics will help "spread the message" which would not be allowed to remain in pages otherwise.