Hey, thanks for the report. I checked, and right now on cursor.com, agent response ratings aren’t being saved if Privacy Mode is enabled on the account. That’s why Couldn't save your feedback shows up every time. It’s not related to your browser or your setup.
I’ve passed this along to the team. I’ll reply here when there’s an update.
For now, you can open this same agent in the Cursor app in the Agents window and leave a rating there. That should work. Let me know if it doesn’t work there either.