Some things need saying at the top of every page. Maintenance on Saturday. A breaking change in the next release. A migration deadline. A conference you are at this week.
None of them are worth a deploy, and all of them are the kind of thing that gets left up for three months after they stop being true.
Write it in Settings
A Smart Bar is a strip of content across your knowledge base. You write the message, pick the colours, choose whether it sits at the top or the bottom, and it appears for readers — no code, no deploy, no involving anyone who knows what a build is.
Because it takes rich content rather than plain text, you can put a link in it, which is usually the point: the banner says there is a breaking change, and the link goes to the page explaining it.
Give it an end date
This is the part that matters more than it sounds.
Announcements have a scheduling option: a start date and an end date. Outside that window the bar is simply not served — the schedule is enforced on our servers, not by hiding the element in the browser, so an expired announcement is genuinely gone rather than sitting in the page waiting to be spotted by someone reading the source.
Set the end date when you write it. The banner about last month's maintenance window takes itself down, and nobody has to remember.
Match your site
Background, text and link colours are yours to set, along with a border colour and a light or dark treatment, so the bar reads as part of your documentation rather than a notification bolted on top. A maintenance notice can be quiet and grey; a breaking-change warning can be loud.
You can run more than one, and control where each appears — across the whole knowledge base, or scoped to particular pages when the message only applies to one area.
Where readers see it
Announcements appear across your documentation — the home page, article pages, category pages and the glossary — including when your site uses the Portal landing page as its front door, which for many knowledge bases is the page most readers actually arrive on.
A note on restraint
Banners work because they are unusual. A knowledge base with a permanent announcement bar has trained its readers to ignore the top of the page, which means the one time it matters, nobody reads it.
Use them for things that are genuinely time-bound, give them an end date, and let them disappear.
Where to find it
Announcements live under Settings → Appearance → Smart Bars.