I can't find the Text Nodes in Natron anymore. I am running Natron 2.0.3 in another system which have them, but in this system it doesn't. I am not sure how many more nodes are missing.
I am running Natron 2.1.7 Devel in Archlinux 4.8.6-ARCH kernel.
You need the openfx-arena package.
Thank you, that did it!
I'll request they put this package as dependence in the archlinux AUR repository.