UWP: OneNote UWP Attachments are Read-only, How to Edit Attachments?

Question:
In OneNote for Win 10, the Word and Excel attachments inserted in notes are read-only, why? How to edit the attachments?

Answer:
OneNote for Windows 10 runs in a separate sandbox. Unable to communicate directly with external programs.

OneNote's traditional attachments can be opened with local App, but they are impossible edit and save back to OneNote.

Solution:
In order to be able to use editable attachments.
You can save attachments as new OneNote’s cloud attachments.
Then use Gem Menu for OneNote UWP add-in to open the cloud attachment for editing.
This solves the annoying problem that the OneNote for Windows 10 attachments have not been editable all along.
 
MAC: How to Enable/Disable Cloud File Attachment in OneNote (Apple Version)?


Final Solution:
2019-3, OneNote UWP upgraded to 16001.11328.20100.0, starting to support opening traditional attachments for editing.