Unable to open 3 VS Code windows attached to the same Docker container

I have a Docker container with OrbStack that contains a directory repos with a repository app-main and worktrees like app-feature-a to develop in parallel. Configuration is done in order to prevent modification of the container configuration file in the ruing Docker.

project/
├── .devcontainer/     # outside the mount, on purpose
│   └── devcontainer.json
└── repos/
    ├── app-main/
    ├── app-feature-a/
    └── app-feature-b/

MWE for devcontainer.json :

{
  "name": "myproject",
  "image": "mcr.microsoft.com/devcontainers/base:ubuntu",
  "workspaceMount": "source=${localWorkspaceFolder}/repos,target=${localWorkspaceFolder}/repos,type=bind",
  "workspaceFolder": "${localWorkspaceFolder}/repos",
  "remoteUser": "vscode"
}

source and target are identical to support the absolute paths linking the worktrees.

Steps I have followed:

1. Open a first VS Code window and use it to create the container using Dev Containers: Reopen in Container. The badge on the bottom left reads Dev Container: myproject

2. Open a second window, run Dev Containers: Attach to Ruing Container, choose the container and open folder app-feature-a. The badge reads Container vsc-... (I don't really know why the badge is different by the way).

3. Try to repeat step 2 but instead of coecting the third window, it just focuses back to the second window.

4. Or from one of either 2 windows, run Open Folder in Container but it then asks to add a configuration, so it won't coect to the existing container.

Is there a way to have more windows coected onto the same container, in order to work on more than 2 worktrees in parallel?

Using one container for each worktree could work but would be a hassle.