Testing with: - `7.1.0a0`, `7.1.0a1` or `7.1.0a2` (or newer) - A custom drive, for example https://github.com/jupyterlab/jupyterlab-github/ The default file browser on the tree page tries to create files and directories in the installed drive, instead of the default file browser: [notebook-drive-issue.webm](https://github.com/jupyter/notebook/assets/591645/0e1b436d-4245-43a7-a01f-4ffc9b30ff7d) Looking more closely, the model seems to be pointing to the custom drive (`GitHub:`)  This is not an issue with `7.0.6`, so this is likely related to a change in the JupyterLab 4.1 pre-releases, or in some PRs targeting Notebook 7.1. Also this does not appear to be an issue in JupyterLab: [jupyterlab-create-new-folder-context-menu.webm](https://github.com/jupyter/notebook/assets/591645/3d412da9-c827-4d49-9027-ca6476d767c6)