Can't upgrade tuba due a gpg key error

[Yochanan]

Please read the pinned comment on the tuba AUR page:

GPG Error

Import the gpg-key with:

curl -sS https://github.com/GeopJr.gpg | gpg --import -
curl -sS https://github.com/web-flow.gpg | gpg --import -

See also the pinned tutorial here in the AUR section:

AUR package fails to verify PGP/GPG key: “unknown public key”, “One or more PGP signatures could not be verified!”

Summary If you get llvm-5.0.1.src.tar.xz … FAILED (unknown public key 8F0871F202119294) then gpg --recv-key 8F0871F202119294 and try again. Enter the key ID as appropriate. Detail Many AUR packages contain lines to enable validating downloaded packages though the use of a PGP key. This establishes a level of trust between the software author and anyone who downloads the software - if you trust the key, and the download validates against the key, then you can trust the download. Pacman ha…