src/vs/workbench/services/dialogs/browser/abstractFileDialogService.ts/AbstractFileDialogService/defaultWorkspacePath
class AbstractFileDialogService:	async defaultWorkspacePath(schemeFilter = this.getSchemeFilterForWindow()): Promise<URI> {
		let defaultWorkspacePath: URI | undefined;

		// Check for current workspace config file first...
		if (this.contextService.getWorkbenchState() === WorkbenchState.WORKSPACE) {
			const configuration = this.contextService.getWorkspace().configuration;
			if (configuration?.scheme === schemeFilter && isSavedWorkspace(configuration, this.environmentService) && !isTemporaryWorkspace(configuration)) {
				defaultWorkspacePath = resources.dirname(configuration);
			}
		}

		// ...then fallback to default file path
		if (!defaultWorkspacePath) {
			defaultWorkspacePath = await this.defaultFilePath(schemeFilter);
		}

		return defaultWorkspacePath;
	}