I am using Chrome v52.0.2743.116 on OSX v10.11.6 and am unable to search the docs on ReadTheDocs.io. This is making it very difficult to learn RedPotion and its associated gems. I hope the maintainers of those projects are able to fix the issue or move to a different system to host their documentation.
I recommend you contact the ReadTheDocs.io support, Im sure they will want to fix this.
Additionally, you can open an issue in the RedPotion repo.