I spent quite a while trying to get Slack notifications working based on the instructions on the Jenkins Wiki. They do not work.
The instructions on GitHub work great, so I added the following warning to the Jenkins Wiki page:
The instructions presented below are incomplete. Follow the instructions on the Slack Plugin's GithHub home page. They work great.
Please shorten the Jenkins Wiki instructions to refer the user to GitHub.
If you agree that this should be done, just assign this issue to me, and I will edit the Jenkins wiki for you.