Port Forwarding in VS Code is unstable

[lalver1]

When debugging the app, port forwarding in VS Code is unstable and in some situations it prevents the user from being able to access the application in their browser.

To Reproduce

Steps to reproduce the behavior:

1. In VS Code, close all ports, reopen the folder locally, and rebuild the container to start with a fresh dev container, notice the two forwarded ports
   
2. Run the VS Code debugger using the Django: Benefits Client launcher configuration, notice that a third port was added
   
3. In your web browser, navigate to the app running on localhost:DJANGO_LOCAL_PORT where DJANGO_LOCAL_PORT is set in your .env file.
4. Select a Transit Agency and submit the form Choose this benefit with Agency cardholder selected. Notice that a new port has been added
   
5. The web browser hangs
6. Stop the debugger
7. Restart the debugger. Notice that the forwarded addess has changed, the browser is still hanging

Expected behavior

The web browser should still be able to reach the application on localhost:DJANGO_LOCAL_PORT

Screenshots

Similar behavior occurs with VS Code running on Linux although the Forwarded Address and Running Process columns look slightly different from VS Code running in macOS.

Desktop

• OS: macOS Sonoma
• Browser: Firefox
• Version: 134.0.1

Additional context

A possible solution is to add "otherPortsAttributes": { "onAutoForward": "ignore" } to devcontainer.json as suggested by https://stackoverflow.com/a/74177846. A description of the otherPortsAttributes property is provided at https://containers.dev/implementors/json_reference/#general-properties and the options that the property can take are shown at https://containers.dev/implementors/json_reference/#port-attributes.
While adding "portsAttributes": { "onAutoForward": "ignore" } could also be a solution, adding this did not make any difference in contrast to adding "otherPortsAttributes": { "onAutoForward": "ignore" }.

[machikoyasuda]

Going to test this possible solution out locally. Thank you for investigating and writing this all out.