The OneNote for Mac application 16.43 (20110804) will lag or crash on Mac OS Catalina 10.15.6 and Mac OS Catalina 10.15.7. When typing notes or using a pen to take notes in the OneNote for Mac application and using the Mac split-screen feature or not using the Mac split-screen feature, the OneNote for Mac application 16.42 (20101102) and Meanwhile, I’d like to update the summary of the In your environments for further investigation.

Given the situation, I kindly suggest you u se the feedback tool in the upper-right corner of your app to our related team as soon as possible so that they can be aware of the issue in the latest version number of the OneNote for Mac application Thanks for your updates and letting us know that the issue persists in the latest version of the OneNote for Mac application 16.43 I'm glad to hear that the issue goes away on your new Mac in your environment and provide the possible root causes here.