This is not a release version, though, is it? Or has some additional extensions on top of it?

I've had bad experiences on the latter, as in a lot of breakage occurred :/.

Looks like a dev build of the 1.1 release

I do have FreeCAD Ribbon addon, but I think the rest is as is. Indeed, it is the development version and it is stable, but I'll probably switch to 1.1 stable once it is released, just so that I automatically get the package from my distro.

...which is Arch, by the way :D