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

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

		const parent = await this.getParentDirectoryHandle(uri);
		const name = extUri.basename(uri);
		return await parent?.getFileHandle(name);
	}