prevent annotation overlays from being clipped by browser window

annotation overlays get clipped by the browser window. needs to be repositioned to avoid this. 

screenshot shows the top right of a header.

<img width="976" height="444" alt="Image" src="https://github.com/user-attachments/assets/767bb29a-0ae5-45e8-b30b-af3add5e99d7" />