Ready, Set, Bake: Ubuntu 20.04 LTS is Now Certified for the Raspberry Pi - OMG! Ubuntu
Status of Ubuntu MATE 18.04 for Raspberry Pi 3 B & B+? - Raspberry Pi - Ubuntu MATE Community
RaspEX especially for Raspberry Pi 3 Model B+ – based on Ubuntu 18.04 LTS – with OpenCPN 4.99.0 pre-installed ::: Build 180331 | RaspEX for Raspberry Pi 4, Pi 3 and Pi 2
Ubuntu for Raspberry Pi 3 B+ - Linux, macOS and Everything Not-Windows - Linus Tech Tips