The documentation is generated in the gh-pages branch in your repo, and you might have to instruct github to use that branch in your repo settings. Have you set the secrets up correctly in travis and github so that the documentation is being built and pushed to your gh-pages branch correctly?
There are a couple things I’m still confused about:
Regarding Documenter{TravisCI}(), what does TravisCI have to do with docstrings or Documenter.jl? I’m getting Travis build reports for my unit tests on each commit, so Travis authentication isn’t the issue.
Is gh-pages a web-hosting thing I have to sign up for or is it somehow living inside the project repo?
The documentation is built and deployed by the CI that’s why it is used with Documenter. If I recall correctly the stable documentation will only be available after you tag a release. Before that you should still have the dev button.