The streaming video platform Roku says that it has uncovered a new data breach impacting 576,000 accounts. The company says it uncovered the new “incident” while investigating last month’s security breach, in which 15,000 accounts were compromised. “After concluding our investigation of this first incident, we notified affected customers in early March and continued to monitor account activity closely to protect our customers and their personal information,” the company said in a statement. “Thr...