> Thanks for the detailed report and reproducible example, and sorry for
> the late reply.  Fixed in 36233d976d.

That works! Thanks.

But, a new bug seems to have been introduced or was already there.

When the publishing directory does not already exist (in my case,
~/.emacs.d/org-tangle-bug/pub), I get

(file-error "Opening output file" "is a directory"
"~/.emacs.d/org-tangle-bug/pub/")

If I'm correct, org-babel-tangle-publish should create the publishing
directory if it does not already exist.

Just like earlier, I have attached a tarball with org files and emacs
lisp code to reproduce the bug. Just extract the tarball, and run

emacs -Q -l minimal-org.el