Problem using a Wacom tablet in PowerPoint Slideshow mode

Hi @Tim Gallagher, 

Good day to you! Welcome to Microsoft Q&A. 

Thank you for bringing this to our attention, I truly understand how disruptive it is to have horizontal lines displayed when writing in PowerPoint in slideshow mode. Your experience that horizontal lines randomly appear, which has been reported by our users, and I appreciate your patience. While this is by design,  I agree that there’s room for improvement. I’ve shared your feedback internally, and I’d also recommend submitting it directly through the Microsoft Feedback Portal so it can be reviewed and prioritized by the product team.   

As moderators in the community, please be aware and accept that we are not responsible for the design of the product and that we have limited resources for detailed information about Microsoft products. We help guide users to the appropriate channels but do not influence product design decisions.    

I recommend submitting your feedback via the Microsoft Feedback Portal or directly through any Microsoft 365 app by going to Help > Feedback or File > Feedback. Feedback with more votes is more likely to be reviewed and considered by the product team for future updates.   

Later on, the development team will put it into Microsoft 365 Roadmap | Microsoft 365   

Your feedback is valuable and contributes to the ongoing improvement of Microsoft 365 products. If there’s anything else I can assist you with, please don’t hesitate to let me know.     

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