src/vs/workbench/contrib/files/browser/fileImportExport.ts/ExternalFileImport/import
class ExternalFileImport:	async import(target: ExplorerItem, source: DragEvent): Promise<void> {
		const cts = new CancellationTokenSource();

		// Indicate progress globally
		const importPromise = this.progressService.withProgress(
			{
				location: ProgressLocation.Window,
				delay: 800,
				cancellable: true,
				title: localize('copyingFiles', "Copying...")
			},
			async () => await this.doImport(target, source, cts.token),
			() => cts.dispose(true)
		);

		// Also indicate progress in the files view
		this.progressService.withProgress({ location: VIEW_ID, delay: 500 }, () => importPromise);

		return importPromise;
	}