[OS X Emacs] New problem with MELPA on Aquamacs

[Win Treese]

> On Jan 4, 2021, at 11:59 AM, Robert Goldman <rpgoldman at sift.info> wrote:
> 
> I tried to install the MELPA package conda, version 20200818.1614. This failed, and I see this in *Messages*:
> 
> package-install-from-archive: https://melpa.org/packages/f-20191110.1357.el: Bad Request

Hi, Robert. This looks pretty mysterious, and I think the following will correct it:

(setq gnutls-algorithm-priority "NORMAL:-VERS-TLS1.3”)

This has to do with how the SSL/TLS protocol is negotiated between Aquamacs using GNUtls and the MELPA server, and it shows up as a “Bad request” error.

If anyone is interested, if you set url-debug to t, it tells you a lot about what is going on under the covers for web requests, although it doesn’t by itself tell you enough to figure out the TLS thing.

Aquamacs 3.6 will have this set by default.

 - Win