That's rather a large jump in versions, and there's some hiccups.
The best thing you can do is plan for doing at least two phases as the absolute minimum you should to is to take 2.10 to 3.5 and then 3.5 to 5.x - it's really not funny trying to upgrade 3.4 or below to 4 or 5 without going to 3.5 first.
Basic principles though:
Hi my Community friends! For those who don't know me, I'm a product marketer on the Confluence Cloud team - nice to meet you! For those of you who do, you know that I've been all up in your Co...
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