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Recently, we found that if we disable the fast startup of windows settings. This problem never happened again.
It's hard to say, the windows fast start up is very complex system, it may cache some temp data during machine turn off. But there is not document telling it will cache ink strokes. I also test with photo app draw function, unfortunately we can't reproduce your problem. you could make a blank app and detect if the problem is related with clear method. or share your code here. And you could also report this problem with windows feed back app.
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