Possible deploydocs() misconfiguration: main vs master Documenter's configured primary development branch (`devbranch`) is "master", but the current branch (from $GITHUB_REF) is "main". This can happen because Documenter uses GitHub's old default primary branch name as the default value for `devbranch`. If your primary development branch is 'main', you must explicitly pass `devbranch = "main"` to deploydocs. See #1443 for more discussion: https://github.com/JuliaDocs/Documenter.jl/issues/1443