Something is wrong with the way the tags are showing up / setup on the site.
First Issue -
When I click on "Support" it opens "Dev" which has the sub category "Installation" under it. When I click on Dev I see extensibility / theming etc.
Second issue -
When I click on the installation sub tag and try to create a new discussion, the compose window comes up with the installation subtag. However when I try to post the discussion, it gives me an error saying I need to select a primary tag. Have to then click on the installation tag and then add the primary support tag.
Not sure if this is a setup issue or a bug. Happy to duplicate on my test forum if more information or a github issue is required.