expired GPG key for TeX Live 2020

[dany111 at email.it]

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  > Norbert proposes adding the texlive.asc public key to the TUG Web site.
    I support that.

I strongly support that, too. In this way, you can download the public key directly from the TUB website, download the iso from a mirror  and verify sha512 signature without problems. I spent a lot of time trying to retrieve the key and this will resolve the problem.

Thanks Norbert for uploading the key in the ubuntu keyserver. I was able to import that and finally verify the sha512 signature.