To run on Ubuntu just use KVM to run
If you are a bit lazy like me, the idea to reboot your system seems inconvenient. But with the help of QEMU there is an easy to use alternative available. QEMU is a program that allows us to emulate a whole computer inside our running system. Running the Tails system from inside QEMU has it’s drawbacks: If your host system is compromised, so will you virtual machine. The other argument are the traces you may leave behind: But with a full-disk encryption (or even at least for your home-partition), these can be almost mitigated.