ues it's is, since a few days 
You can create a link to a note by specifying its ID in the URL. For example:
[Link to my note](:/0b0d62d15e60409dac34f354b6e9e839)
Since getting the ID of a note is not straightforward, each app provides a way to create such link.
In the desktop app, right click on a note an select "Copy Markdown link".
In the mobile app, open a note and, in the top right menu, select "Copy Markdown link".
You can then paste this link anywhere in another note.