Hello everyone,
We are releasing the next version of the Parsoid deb and npm packages (v0.9.0) later today. There is one significant change in this release that might affect some VisualEditor installations. This version of Parsoid wraps sections in <section> tags and bumps the HTML version to 1.6.1. However, VisualEditor installations older than Dec 12, 2017 are not compatible with this section wrapped output.
In order to prevent silent failures, Parsoid will do a hard fail and reject parse requests with a HTTP 406 when it receives a version string smaller than 1.6.0 (which VE before Dec 12, 2017 would issue). VE will then popup the following error: "Error loading data from server: apierror-visualeditor-docserver-http: HTTP 406. Would you like to retry?" Retries won't help in this scenario.
Knowing this, you have a couple of options:
* Not upgrade Parsoid. If you upgrade Parsoid without reading this notice and later stumble on this (which we'll also add to the Parsoid releases page), you have the option of downgrading your Parsoid install by downloading an older deb package from https://people.wikimedia.org/~ssastry/parsoid/debs/ * If you choose to upgrade Parsoid and your VE installation is from before Dec 12, 2017 (which is probably most of you), the recommended solution is to upgrade your VisualEditor installation as well.
If for some reason you really really need to upgrade Parsoid but cannot upgrade VisualEditor, contact us on IRC in #mediawiki-parsoid to ask us how you can do that.
Subbu.
(on behalf of Parsoid developers).