5.5.4 had a critical flaw in it, so it was pulled to prevent people moving to a broken version.
It's a black and white flaw though - if you haven't hit it by now, you probably won't on your current platform. You could ask https://support.atlassian.com if they'd provide you with a copy, as you probably aren't affected by it, but I'd be looking at moving to 5.5.6+ (5.5.5 was affected too I think)
Hi team, I’m Avinoam, a product manager on Confluence Cloud, and today I’m really excited to let the Community know that all customers can now try out the new editing experience and see some of the ...
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