No way to easily get from the banner to the topic, unless the corresponding post actually has a link to itself added.
If something is important enough to banner, it should be easy to get to the corresponding discussion.
「いいね！」 6
I actually think this is up to moderators, they are the one’s doing the bannering.
Sometimes it may be appropriate to link to the discussion, sometimes, well the banner could be a closed hidden topic.
In the above case they can simply improve the copy to link to the topic.
「いいね！」 2
Revisiting this, would it be possible to add a link that even only mods/admins would see so that we can quickly get to the banner to remove it? That would be a great feature and avoid confusion/searching.
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That’s a great, great idea for a feature – @zogstrip can you add a small font footnote to the banner that only staff can see that says
“edit this banner >>”
and when clicked, takes you to the post?
「いいね！」 3
Just added the link for staff members 
https://github.com/discourse/discourse/commit/90eca69e0a0574e458d6960e90b0eae083e431d3
「いいね！」 4