Been waiting for uBlock Origin support for some time. I'm really glad the developers decided to support it! UBlock Origin seems to be the only suggested add-on in a fresh install. Just tested it briefly, and it seems to work great.
Where does it say it supports ublock? Is there a special build required? Going to AMO it says it's not compatible.
edit: seems like you have to go through settings -> addons to install.
It's built-in, rather than an add-on?
Perhaps it's special because it's a mobile app, and the only way to get the functionality is to have it included? I don't use Android, but there's no add-ons on the IOS version.
Regular Firefox for Android already supports add-ons (including uBlock Origin), this release is for the coming new version, Firefox Preview, which so far didn’t have support for any add-ons.
The non-nightly Firefox Preview for Android doesn't support add-ons. I imagine the title is just to emphasis that add-ons such as uBlock Origin work with this nightly.