Simply opening Simulator app (26.0) causes high CPU usage on macOS Tahoe (26.1). ReportCrash process usage is very high throughout and causes the system to heat up pretty soon. Looking into Console app for the logs found MercuryPosterExtension process is keep on crashing. (Check under Crash Reports) simctl Diagnose https://download.developer.apple.com/OS_X/OS_X_Logs/simctl_Diagnose_Logging_Instructions.pdf Share the Simulator Diagnose report while reporting, Thanks. I have raised a ticket/feedback with Apple. I request all of you to raise one too so this gets fixed soon. Apple Feedback Assistant - FB20985249