storageUri
The uri of a workspace specific directory in which the extension can store private state. The directory might not exist and creation is up to the extension. However, the parent directory is guaranteed to be existent. The value is undefined when no workspace nor folder has been opened.
Use {@linkcode ExtensionContext.workspaceState workspaceState} or {@linkcode ExtensionContext.globalState globalState} to store key value data.
See also
{@linkcode FileSystem workspace.fs} for how to read and write files and folders from a uri.