Description of problem: Some commands are not documented in latest documentation.
Version-Release number of component: dnf.noarch 2.7.5-11.fc28 @updates-testing.
How reproducible: In terminal enter 'man dnf', then search for patterns 'config-manager', '--dump', '--set-enabled', '--set-disabled'.
Actual results: Those commands and options are missing from documentation.
Expected results: Documentation to be up-to date.
Additional info: Applied command 'dnf config-manager --dump --set-enabled updates-testing' is operational.
Source (latest availavle): https://docs-old.fedoraproject.org/en-US/Fedora/26/html/System_Administrators_Guide/sec-Managing_DNF_Repositories.html
Those documentation is directly maintained by dnf team.
The pages that you mentioned above are maintained by community (including me). I also wish that you can also join the documentation community. Please if you can help us with updates that would be really great. Thanks a lot for reporting.