It would be incredibly useful to have support for the OneNote protocol to be able to link to OneNote pages directly. It sort of works already
1. Make sure the comment box is Rich Text and that Word is set to do content format conversions
2. right click a page or paragraph in OneNote and select Copy link
3. Paste into the comments box.
4. The link is clickable and works
5. Navigate to another task and come back to this task
6. The OneNote link is no longer clickable