Your tests then should also work correctly with transactional testing (and no need for database cleaner)

Five years later, the facts on the ground have finally changed. I no longer believe that this bargain is worth it for most new applications.

Lately I've been much happier working with ROM, so it's just as well that Rails is obsoleting this gem.

Rails 7 supports Postgres enums natively (more info)

It is a stepping stone towards ES7 async/await.

most recently the release of ActiveStorage in Rails 5.2

For example, Database Cleaner for a long time was a must-have add-on: we couldn’t use transactions to automatically rollback the database state, because each thread used its own connection; we had to use TRUNCATE ... or DELETE FROM ... for each table instead, which is much slower. We solved this problem by using a shared connection in all threads (via the TestProf extension). Rails 5.1 was released with a similar functionality out-of-the-box.

If you don't need to support IE9 or lower, you can use flexbox freely, and don't need to use floated layouts.