The inaugural release of this fork updates it to handle the latest in Facebonk's vagaries. In particular, it makes it work on the particular post I needed to expand. Hopefully it'll work for you too! If not, create issues and/or pull requests as appropriate. :-)
How to install: Open the file of your choice in your favourite text editor (e.g. Notepad or gnome-text-editor should do fine), select all, copy to clipboard. Then, go to your browser, create a new bookmark (in some browsers you may need to explicitly make the bookmarks bar visible), and paste the copied javascript: URL into the URL field. It should look a bit like this:
The original author, Jens, had a nifty page with a link you could just drag right onto the bookmarks bar. Not sure if I can do that with a GitHub Release. :-P This release of the compressed bookmarklet is about 13.4 kb in size.