A change with no title is displayed with an empty heading

The title of a change is optional: the conventions displayed by the change form say that a Miscellaneous change needs no title, and nothing makes the field mandatory.

The simple and flow change displayers nevertheless always open a section for the change, so a change with no title is displayed under a heading holding no text at all:

<h3 id="H" class="wikigeneratedid wikigeneratedheader"><span></span></h3>

The result is an empty section in the release note and, since the release note template displays a table of contents, an empty entry in that table of contents for every untitled change. Those headings also all share the same generated id="H".

The grid and list displayers already display such a change as its summary alone; simple and flow should do the same.