This extension lets you note something from the page that you are reading, to treenote.tk
Select text on current page, press 'TN' button to save sub note
Next time you visit this page, you can review your main note and sub notes on this page, and select some text to start search positions of them on the page.
Each webpage could have one main note and it's sub notes.
You can go to treenote.tk and review all your notes, too.