Hello Wonseok. Thank you for bringing this up, From what you describe, I believe you are addressing the subtle but perceptible behavior with the mouse cursor as you switch between Korean and English input modes possibly something like cursor jitter, visual flickering, or unanticipated positioning when switching modes. Not a dealbreaker, but an example of the level of detail that UX can affect, especially for multi-lingual users, with comfort and accuracy.
Interestingly, there have been some recent reports aligned to Windows 11 version 24H2 for erratic cursor behavior after Windows updates oversized cursors, or lag in cursor response when waking from sleep or switching input modes. Microsoft acknowledged there were some update issues broadly in August 2025, and provided emergency fixes for KB5063878. They have not officially documented cursor related quirks.
Assuming you would like developer attention on this, I suggest providing feedback directly in the Windows Feedback Hub:
Press Win + F to launch the Feedback Hub
Select Input and Language, or Mouse and Touchpad for the category
If available, include a short video or screenshot
You may help Microsoft prioritize their response in future cumulative updates.
Best regards,