Error Logging: Sentry
You'll need access to a Sentry server to use this functionality; add the Sentry DSN to config/application.yml.
Bundle Analysis: Webpack
To generate the stats.json file that's needed to analyze the Webpack bundle, do the following:
For production:
npx webpack --mode production --profile --json > stats.json
For development:
npx webpack --mode development --profile --json > stats.json
After generating the stats.json, the bundle size could be analyzed by uploading the generated file at any of the mentioned sites here. To know more about how the stats.json looks like, head over to https://webpack.js.org/api/stats/ or you could simply run the command and have a look yourself.