For those that INSIST to use tails, the install script is now working thanks to the reto team recently placing the signature file in the correct location in the release page.
This is the instruction to install debian package on Tails the instructions:
https://github.com/retoaccess1/haveno-reto/tree/master/scripts/install_tails
Easy mode below/ step by step instruction after you already have a tails usb.
Enable Persistance
https://tails.net/doc/persistent_storage/index.en.html
Set up administration mode
https://tails.net/doc/first_steps/welcome_screen/administration_password/
Run this command to download and run the script from the reto repo. Enter the admin password you have setup when requested
curl -x socks5h://127.0.0.1:9050 -fsSLO https://github.com/haveno-dex/haveno/raw/master/scripts/install_tails/haveno-install.sh && bash haveno-install.sh "https://github.com/retoaccess1/haveno-reto/releases/download/v1.0.12/haveno-linux-deb.zip" "DAA24D878B8D36C90120A897CA02DAC12DAE2D0F"
You can then run Haveno by finding the icon in the launcher.
It should connect OK and see yellow or green connection at the bottom.
Create any account.
Reboot tails.
Enable persistence and admin mode again.
Launch tails as you did before and confirm you can connect OK and your account is there.
This is the Haveno-reto public signing key of fingerprint above.
https://haveno-reto.com/reto_public.asc
Addendum.
Reddit seems to block VPNs and has issues with tor as well as easily banning or shadowbanning people if using tor. Monero.town has issues with tor thanks to cloudflare but AT LEAST IT WORKS fine with vpns and is not censored. Consider making monero town your reddit alternative.
If anyone can confirm this is working or exact steps to fix. Need to make it noob friendly as possible. One report that unzip was not found when running the curl command above.