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Safari may show a warning message - "This website is using significant memory. Closing it may improve the responsiveness of your Mac." when you continuously open heavy-contents pages in Smart Review with a high-definition monitor. You may need to (repeatedly) close and re-launch Safari.
EIZO monitors with macOS Big Sur (11.0) is not supported
The current EIZO SDK does not recognize the monitor on macOS Big Sur and does not work properly.