As for the Places Migration Guide — you’re right! I hadn’t noticed that was incomplete. I’ll take a look at that.

Regarding stuff to work on: when I had to embed Gecko for Enso a year or two ago, I had a harrowing time figuring out how to do it, in part because much of the documentation was out-of-date. I’m not quite sure how the documentation has progressed–there’s some mention on the embedding how-to that the reader should just ignore the document and use XULRunner–but maybe cleaning this up could be useful? I’ve heard that WebKit can be embedded using 3 lines of code, so improving our docs could be a good way to keep up with the competition–although if you’re up for something even more challenging, writing some kind of wrapper so that it only takes 3 lines of code to embed Gecko/XULRunner would be pretty awesome too!