Hey, thanks for the request. This is a known limitation. Right now the browser instance is shared across agent sessions, so when they run in parallel they can interfere with each other.
A similar report is here: Agents use the same browser tab, which creates a conflict Agents use the same browser tab, which creates a conflict.
As a temporary workaround, you can stagger browser tasks so only one agent uses the browser at a time. Sometimes an explicit prompt instruction like “open a new browser tab” helps, but it isn’t 100% reliable since the cause is architectural.
The team is aware of the issue. I’ve passed along your feedback, especially for the Agents Window with multi-sessions where this becomes more critical. Let me know if you have any questions.