@ihr
Developing Home Assistant Core in a VSCode Devcontainer I found this link which seems to have worked for me. The trick was to rebuild the Dev Container for ha-core. You can do this by pressing F1 in VSCode whilst in the ha-core repo and selecting ‘Remote-Containers: Rebuild Container’. This worked for me. I verified it by opening the running Docker container on my PC and could see the frontend folder inside the workspaces directory. Hope this helps.