Can't edit and save previously saved sessions

Proxyman version? (Ex. Proxyman 1.4.3)

2.29.0 (22900)

macOS Version? (Ex. mac 10.14)

12.0 Beta (21A5284e)

Steps to reproduce

1. Open Proxyman
2. Record some traffic
3. Save the session to disk and name it "A"
4. Close all the Proxyman tabs and windows
5. Quit Proxyman using Cmd+Q
6. Open the file named "A.proxymansession"
7. Edit the recorded history by deleting some requests
8. Attempt to save changes by tapping Cmd+S
9. Observe beep sound
10. Go to File -> Save Session
11. Give the session a new name "A1"
12. Close all the Proxyman tabs and windows
13. Quit Proxyman using Cmd+Q
14. Open the file named "A1.proxymansession"
15. Observe that the saved session isn't the one that was being viewed and edited and is in fact an entirely new recording

Expected behavior

Saved sessions should act like documents, opening viewing, and editing and saving should be possible. When the only tab open is a saved session Proxyman shouldn't be recording network traffic.

The current behaviour is unintuitive and it doesn't feel like the tab behaviour has really been thought through.

Further info

The use-case is that I want to debug an issue with another app and they have asked for network recording logs. When I record in Proxyman it records more than just the app or domain I care about, when I save a session it saves all traffic not just the filtered view I'm seeing in the interface.

I want to then open the saved session and remove all the redundant requests so that I've just got the ones I care about and save the session before sending it to the app provider to debug the issue with me.