GitHub recently improved security, so you may get the error below like I did when I tried to install oh-my-zsh on a new Mac.
Anton.Perez@amp ~ % sh -c "$(curl -fsSL https://raw.github.com/ohmyzsh/ohmyzsh/master/tools/install.sh)" Cloning Oh My Zsh... fatal: remote error: The unauthenticated git protocol on port 9418 is no longer supported. Please see https://github.blog/2021-09-01-improving-git-protocol-security-github/ for more information. /Users/Anton.Perez Error: git clone of oh-my-zsh repo failed
You can test if it’s because you need to add an SSH key by running:
ssh -vvv firstname.lastname@example.org
You’ll get an error like so if so:
... debug2: we did not send a packet, disable method debug1: No more authentication methods to try. email@example.com: Permission denied (publickey).
If so, just generate a new key and add it to your GitHub account (see this. That’s it!