Don't use this: just use Vivaldi instead. I am no longer actively working on this, so if anyone wants to take it on, please ask and I will transfer the repo.
A simple note panel in HTML and JavaScript - includes a "copy to note" context menu item as well.
Use the Add Note icon - or click inside the lower text box - to add a new note. Notes are saved as you type.
Delete a note by selecting it in the list and clicking the Delete icon.
You can also copy text from a web page to a note using the context menu (but you will need to close the panel: am trying to fix this!)
Works with Opera (Blink engine); possibly other Chromium browsers; and Firefox.
Nab officially for Firefox.
Open source icons from PICOL.