Steps to reproduce

1. Go to http://python-telegram-bot.readthedocs.io/

2. Click on any of the links (for example telegram.ext.updater module)

3. See the empty text

Expected behaviour

There should be a description describing the function etc.

If I the version is set to 'stable' it works:
telegram.ext.updater module

Actual behaviour

There is no description at all

Tried with Chrome and Edge