The Canonical he said that its release Ubuntu 21.04 (Hirsute Hippo) reaches support end next month, on January 20, 2022, urging users to upgrade to the latest version of Ubuntu.
Named “Hirsute Hippo”, Ubuntu 21.04 was released about eight months ago on April 22, 2021, and was the first version of Ubuntu to use Wayland next generation server by default.
It uses Linux kernel 5.11 and the GNOME 3.38 desktop environment (with support for GNOME version 40 applications), Ubuntu 21.04 (Hirsute Hippo) brought nftables as the default firewall, support for smart card authentication, and a redesign for the Yaru dark theme.
However, because it was not a long-term support (LTS) version, Ubuntu 21.04 could receive software and security updates for only nine months, which means it reaches the end of its life on January 20, 2022.
Canonical will then stop offering Hirsute Hippo updates.
After January 20, 2022, Ubuntu 21.04 will become vulnerable to all kinds of threats and attacks, so it is recommended that you consider upgrading to the latest version of Ubuntu, Ubuntu 21.10 (Impish Indri).
The Ubuntu 21.10 comes with a much newer kernel, namely Linux 5.13, full support for the GNOME 40 desktop environment series, Firefox as Snap, support for drivers of her graphics NVIDIA in Wayland session and many other improvements.