If you are using the sidebar plugin and have a header in the sidebar it shows up in the table of contents.  I can see why this happens but it surprised me and wasn't the desired effect in my specific situation. -- [[AdamShand]]

A related side effect: If you use any sort of headers in the page
template (such as placing the page title in an `<h1>`), the toc plugin
picks it up.  I suppose it parses the entire page rather than just the
rendered content. --[[JasonBlevins]]

Why doesn't the TOC appear in the edit page preview?  It only appears when the page is finally rendered.  This makes it somewhat difficult to organize headings, saving & re-editing all the time.  My user page currently has a toc to play with: --[[sabr]]