我在heroku上的应用程序遇到webpacker问题。
日志：
ActionView::Template::Error (Webpacker can't find application.js in /app/public/packs/manifest.json. Possible causes:
2018-07-04T18:47:08.192729+00:00 app[web.1]: 1. You want to set webpacker.yml value of compile to true for your environment
2018-07-04T18:47:08.192730+00:00 app[web.1]: unless you are using the `webpack -w` or the webpack-dev-server.
2018-07-04T18:47:08.192733+00:00 app[web.1]: 2. webpack has not yet re-run to reflect updates.
2018-07-04T18:47:08.192734+00:00 app[web.1]: 3. You have misconfigured Webpacker's config/webpacker.yml file.
2018-07-04T18:47:08.192735+00:00 app[web.1]: 4. Your webpack configuration is not creating a manifest.
2018-07-04T18:47:08.192737+00:00 app[web.1]: Your manifest contains:
2018-07-04T18:47:08.192738+00:00 app[web.1]: {
2018-07-04T18:47:08.192740+00:00 app[web.1]: …