Launched last year on April 13, Ubuntu 17.04 was a powerful release, both inside and outside, running the latest (at that time) stable Linux 4.10 kernel series and shipping with an up-to-date graphics stack based on Mesa 17.0 and X.Org Server 1.19 series. It was also the last Ubuntu release to ship with the Unity 7 desktop by default.
Canonical urges all Ubuntu 17.04 users to update their installations to the latest Ubuntu 17.10 release, as it won't release patches for Meltdown and Spectre bugs. Unfortunately, at least for Unity 7 fans, Ubuntu 17.10 ships with the GNOME 3.26 desktop by default. However, some of their Unity 7 settings will be saved after the upgrade.