Hi, StephenElwell-Sutton
Welcome to the Microsoft community.
Regarding performance response issues, you can visit this website and try turning off these three features.
edge://settings/system
I also suggest checking your extensions and temporarily disabling all of them to see if the issue persists. If the problem continues, it might be a compatibility issue with a specific Edge version. You can try using the Canary version of Edge to see if the issue occurs there. Additionally, please report your issue to the Edge developers using Alt+Shift+I, including your CPU and GPU models.
Best regards
Tommy Jin | Microsoft Community Support Specialist