As part of my recent investigations in the new Gutenberg editor for WordPress I came across a cheeky little error that had me stumped for a while.
Now, I saw this issue whilst running on a local VVV setup, that I’d created solely for this Gutenberg investigations, and as such it was running on an nginx server. I had also not tweaked the default permalinks settings.
To get it working, all you have to do is set a more fancy permalink structure, such as http://local.wordpress.dev/sample-post/.
It seems the issue is to do with PUT request support in the default nginx config, and the way the WordPress REST API works out-of-the-box. If you want more info, follow that trac ticket above.
I hope to be writing more on my Adventures in Gutenberg, especially my work on adding support for it to the Widgets on Pages plugin.