Thank you for the provided information. I confirm that the bug has been traced back to this Windows update. We installed in on our testing machines and we were finally able to reproduce it.
Here's the Microsoft discussion on the exact issue, that is affecting the Scheduler implementation (since it uses the DrawToBitmap method internally):
Unfortunately at the moment we can't provide any workaround aside from reverting the update, since this is an issue we don't have any control over. We will actively follow the status of this issue, and will update you if a fix or a workaround is provided.
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