I just noticed a bug.
I’m in the parent category Tiago | Music and I click the Sir Giant sub category. It shows the banner. Then I click one of the sidebar “documentation” links to go to a tags page Announcements. When I click the General Discussion link that takes me back to the root of the sub category Sir Giant, the banner is now gone.
The first time I went to Announcements, no banner. When I go to the tags page Music and then back to Announcements, the banner is now visible.
I also just noticed something: if I’m in the Announcements page and I see no banner, if I click the same link again (Announcements) the banner shows up, which is clearly a bug.