AllowInIframe:
This is a path page with a path diagram.
The path page has an embedded tool - path diagram editor, which has its separate toolbar (maybe hidden - look for ยป button, above the path diagram on the left).
A path page may have additional text below the path diagram.
Exclude node summary :
You can edit/modify a path diagram alone without going to page edit mode.
Expand the path editor toolbar, if hidden. Click on 'Start editor', edit the current path diagram and save. The modified path diagram in saved in your file-space. So, the current path will display your saved path diagram in it only if - you were the author of the current path page and you saved the path diagram with its old name!
To load any of the path diagrams saved in your file-space, start the editor first, click the 'Open path diagram' button and click a file name in the list loaded from your file-space.
You cannot load/modify path diagram from others' file-space. However, you can save path diagram from any published page and edit the copy saved in your file-space.