bug#36447: 27.0.50; New "Unknown keyword" errors

[Pip Cet]

On Mon, Jul 1, 2019 at 12:26 PM Noam Postavsky <npostavs@gmail.com> wrote:
> does not give me an error.  Is it possible that it was just the 'make
> bootstrap' which fixed things?

Just as a data point, I saw similar problems ("unknown keyword :group"
errors) that went away after either of `make bootstrap' or
re-evaluating custom.el (and installing non-compiled versions of it).

So either something changed incompatibly about our bytecode, or some
recent versions of emacs must have miscompiled custom.el.