When I double-click (or drag) the Header item above, the tags that you see in the tooltip are created. That's really great, because now I'll never need to type those tags again.
The tooltip that you see above is of the same kind as the ones I raved about exactly two months ago, in Tooltips Like Never Seen Before. They're defined in Bundle.properties files, referenced in the XML file that collects all the resources for a tag, which in turn is registered in the layer.xml file. Here's the definition of the above tooltip:
And this is the relevant method in my code snippet definition:
Finally, this is the result of dragging the new code snippet into the page: