Adding authentication provider results in "Unknown provider."

Community Packages Providers
7

New findings.

Adding the following line to src/extensions/users-permissions/strapi-server.js changed the error

“Unknown provider.” → “404 Not Found”

"use strict";
module.exports = (plugin) => {
  console.log("strapi-server.js", plugin.services);
  plugin.bootstrap = require("./server/bootstrap");
  plugin.services["providers"] = require("./server/services/providers");
  plugin.services["providers-registry"] = require("./server/services/providers-registry"); // new 
  return plugin;
};