src/vs/platform/extensionManagement/common/extensionStorage.ts/ExtensionStorageService/migrationList
class ExtensionStorageService:	private get migrationList(): [string, string][] {
		const value = this.storageService.get('extensionStorage.migrationList', StorageScope.APPLICATION, '[]');
		try {
			const migrationList = JSON.parse(value);
			if (isArray(migrationList)) {
				return migrationList;
			}
		} catch (error) { /* ignore */ }
		return [];
	}