We have some apps that have moved to Heroku Enterprise and we have new domains for them.
However, now when using heroku open or the "Open app" button in the app dashboard, I am directed to the default domain instead of the custom domain.
Is there an easy solution to this on my side, or is it a bug, perhaps?
This is an expected behaviour.
Whenever you use use
heroku open via Heroku CLI or click the "Open app" button on the Heroku dashboard, you're always going to be directed to the
[your-app-name].herokuapp.com url of the app.
While your app has a custom domain, using those Heroku shortcuts will not automatically redirect you to those custom domains.