In pull-request, we should diff against ${{ github.event.pull_request.base.sha }}

[praiskup]

Not against the (possibly updated) freshly checked-out origin/main branch.

This is the problem:

vcs-diff-lint-action/container/cmd

Line 69 in 0d6348a

git fetch origin "$target_branch:$target_branch" &>/dev/null

The generated diff might be unnecessarily big if a different pull-request was merged in the meantime.