How to delete a view named ".."
Just as I was finishing this question, I had another idea which was successful. I found by accident that "https://{account}.ci.cloudbees.com/view/../delete" will delete the default view. Another test confirmed that "https://{account}.ci.cloudbees.com/delete" deletes the default view.
- In "Manage Jenkins", set ".." as the default view.
- Enter "https://{account}.ci.cloudbees.com/delete" into the URL bar.
- Go back to "Manage Jenkins" to set a new default view.