Those secret screens generally display information that most people wouldn't understand and would just cause more confusion and questions. If it didn't work, try again. You have to complete the sequence within a short period of time. Also, those secret screens can be removed at any time, but I just tried it and it still works.
Is there a reason you want to check the temperature? Are you getting a message about overheating?
Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution." If you appreciate my answer, maybe give me a Kudo.