OneNote Gem Add-Ins

MAC: How to Save Selection as HTML in OneNote?

Gem Menu for Mac OneNote 1.0 offer Save As feature, save the selection in Mac OneNote to a HTML file.
Step 1: Select Content in Mac OneNote

At first, select some content in Mac OneNote.

You can use keyboard shortcut to quickly select OneNote content.
Press once ⌘ (command) + A, OneNote will select current paragraph.
Press ⌘ (command) + A again, OneNote will select  the content of current container.
Step 1: Select Content in Mac OneNote
 
Step 2: Click Gem Menu Save As HTML File

Then, click Gem Menu -> "Gem" -> "Save As" menu item.
It will pop up SAVE AS window, specify the folder and .html file name, finally, click "Save" to save .html file.

Demonstration
Gem Menu for Mac OneNote save selection in Mac OneNote as HTML file.
 
Download Gem Menu for Mac OneNote