Hi @Joakim_Warholm! Welcome to the Community forum 
When you mentioned wanting the agent to give you the usual environment toggle, could you clarify what you were expecting the agent to do/show?
In the new app builder, you can manually toggle between environments in the lower left corner of your app.
Since the new app builder is still in beta, there are still features that are not available yet but we are working on adding! One feature that may help you out here is shareable preview links, which will allow builders to try out the app ahead of publishing (more info here).
Hope this helps! If you have additional questions let me know!
-Jen