Very interesting. All prerequisites for detachment are met, but you don't get detachment. Hypothesis: Maybe the WindowServer attempts to detach, fails, and then reports the error somewhere, and the error reporting is what's causing the CPU usage.
Bug 1738926 Comment 37 Edit History
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Edit: this comment is wrong Very interesting. All prerequisites for detachment are met, but you don't get detachment. Hypothesis: Maybe the WindowServer attempts to detach, fails, and then reports the error somewhere, and the error reporting is what's causing the CPU usage.