The list of available fixtures is created every time you hit the Edit button. The page you are editing is searched for !fixture directives. These directives name the fixtures to be included in the list, one fixture per directive.

!fixture fitnesse.fixtures.PageCreator

Parent pages are also searched for !fixture directives, so if you have a parent project page you can put all the !fixtures there.

The old method of searching the FixtureList page still works, but is deprecated.