src/vs/platform/files/browser/htmlFileSystemProvider.ts/HTMLFileSystemProvider/getDirectoryHandle
class HTMLFileSystemProvider:	private async getDirectoryHandle(uri: URI): Promise<FileSystemDirectoryHandle | undefined> {
		const rootUUID = getRootUUID(uri);

		if (rootUUID) {
			return this.directories.get(rootUUID);
		}

		const splitResult = split(uri.path);

		if (!splitResult) {
			return undefined;
		}

		const parent = await this.getDirectoryHandle(URI.from({ ...uri, path: splitResult[0] }));
		return await parent?.getDirectoryHandle(extUri.basename(uri));
	}