I'm pretty sure it's Illustrator triggering the problem, although I usually have InDesign running at the same time, but rarely if never notice the fan blowing at high speed when only InDesign is open.
This has been happening for many months. Illustrator 24.2.1 running on Mac OS 10.5.6. It's intermittent and seems to occur most often when Illustrator is in the background.
I have tried the two fixes at High CPU usage due to CEPHtmlEngine and they have not helped.
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