I still had to change the structure of the translation files and then request the translation components to be set up on Weblate. But, now it is done and you can start translating the manual here: https://hosted.weblate.org/projects/tiled/
The “Tiled” component is the application itself. The other components are part of the manual:
Documentation Index: A small component covering just the index page of the documentation.
Manual: The actual Tiled Manual
Reference: The reference pages, which are documenting the TMX format, its changes over time and the list of libraries and frameworks supporting it.
Weblate will commit any translations you’re doing to its local git repository. If you would like to see your translation updated at http://tiled.readthedocs.io/fr/latest/, just ask me to merge the changes into the main repository, after which readthedocs.org will automatically rebuild it.
I would suggest that while translating, you keep the documentation at http://tiled.readthedocs.io/en/latest/ open alongside to have a better sense of the context of the things you’re translating.
Since you’re the first to go about this, let me know how it goes! If this approach works well then we can probably find translators for some other languages as well.
Finally just a note of warning, that the original documentation is still quite out of date in some places and I will be rewriting parts of it, which will of course require the translations to be redone later.