When working with devicetree files, it is easy to accidentally make a change in a source file that belongs to the nRF Connect SDK when you really meant to make the change in a file that belongs to your application.
One common example of such a pitfall is when you forget to define an overlay file and start working directly on the board file of a development kit. If you maintain your own board files, this is still a valid usage scenario, but if you do not, you might end up breaking other applications.
To help avoid this, the extension now warns your if you are about to edit a board file under the nrf or zephyr directories in the SDK. Hovering over the warning shows a tooltip from which you can create a new overlay file. The button works the same way as the corresponding option in the Details View.