Just updated from 0.19.3 to latest version 0.20.4

When running
dokku enter app
nothing happen.

I realized it is working fine running
dokku enter app web

Noting I only have one single container type defined (web) and dokku enter app was working on 0.19.3

Additionally, you can run enter with no container-type. If only a single container-type is defined in your app, you will be dropped into the only running container. This behavior is not supported when specifying a custom command; as described below.

(as notified here)

normal behaviour should be that
dokku enter app
automatically select the web process if this is the only one (or maybe alert to notify a process name is required)