Wew, new Ubuntu LTS... I stopped using Ubuntu years ago. Let me recount the ways it has stricken me.
broken packages 🙁
uniquely maintained patches from upstream ☹
massive test suites disabled 😦
hidden bugs from said patches and disabled suites 😢
get stuck on LTS because upgrades are a nightmare. 😭
I'm literally still running 12.04 on a (non-web facing) server somewhere because there's no upgrade path without a full rebuild.