[ocaml-platform] opam update problem

[Bruce Butterfield]

I'm unable to run 'opam update' -- I get an error message "Could not update repository default". Running it with debug flag:

$ opam update --debug
...
Processing  1/1: [default: http]
00:00.397  PARALLEL                Collected task for job 0 (ret:256)
00:00.397  SYSTEM                  rmdir /var/folders/6p/sf2lk3297kb9sl_tpq6tckcw0000gn/T/opam-90980-dd682e
00:00.403  SYSTEM                  Could not download file at https://opam.ocaml.org/urls.txt.
[ERROR] Could not update repository default
...

The period at the end of the URL is suspicious but I have no idea why it is there or if that is the problem. Any ideas?