If a user is viewing a tab such as View, Edit or Attachments, the tab should be rendered as text instead of as a link. Having the Edit tab enabled while editing provides an opportunity to accidentally lose all recent changes.

When editing a page and user clicks to revisit the edit page, they loses all changes since their last draft save. Since the Preview sub-tab view resembles the View tab view, users must remember to click the Wiki Markup or Rich Text sub-tab instead of the Edit tab or they will lose work.

Ideally, the user should not be able to click a tab they are already viewing.