Add XWiki headings WYSIWYG Add/edit Link dialog

The Add/edit Link dialog in the WYSIWYG editor doesn't display XWiki headings as candidate link targets.

I'd like it to do this because the name of the element that serves as the anchor has to be derived by a user-unfriendly process of starting with H, adding the heading text with all of the spaces eliminated, and then, if another heading with the same text also appears in the document (or will after it's rendered), adding -N, where N indicates how many other identically-worded headings appear before it in the document.

Of course, it would have to know about any headings that might be included from other documents and... ugh.