I installed the plugin in the nodebb directory using npm, and also via the admin/extend/plugins (I don't know what the difference between the two methods!)
Although I couldn't access its panel and the log reads:
2020-03-14T14:48:16.847Z [4567/31500] - [32minfo[39m: [socket.io] Restricting access to origin: xxxxx:*
2020-03-14T14:48:17.596Z [4567/31500] - [32minfo[39m: Routes added
2020-03-14T14:48:17.598Z [4567/31500] - [31merror[39m: [plugins/emailer-mailgun] API key or Domain not set!
2020-03-14T14:48:17.604Z [4567/31500] - [32minfo[39m: NodeBB Ready
2020-03-14T14:48:17.610Z [4567/31500] - [32minfo[39m: Enabling 'trust proxy'
2020-03-14T14:48:17.614Z [4567/31500] - [32minfo[39m: NodeBB is now listening on: 0.0.0.0:4567
(node:31500) UnhandledPromiseRejectionWarning: Error: ENOENT: no such file or directory, open '/var/www/xxxxxx/nodebb/build/public/templates/admin/plugins/emailer-mailgun.js'
(node:31500) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:31500) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
I installed the plugin in the nodebb directory using npm, and also via the
admin/extend/plugins(I don't know what the difference between the two methods!) Although I couldn't access its panel and the log reads: