The site has this banner right now that there is an ongoing maintenance:
I couldn't find this post because it isn't tagged maintenance but it's a good time to bump it.
So the bug in the read-only banner in the notification-bar is still there. If you click the ending link: our recent meta posts on the topic.
You are taken to MSE with search containing two repeated tags (the latter having been synonymized to the former) and the
or search operator i.e.
[maintenance] or [maintenance]:
There's no need to keep the second tag lengthening the URL and have a pair of repeated tags in the search box.