Google will end support for the Google Keep Chrome app in February 2021. The app is being moved to Google Keep on the Web, from where it can still be accessed. Access to Keep on the Chrome OS lock screen will also not be available anymore.
Source

Google will end support for the Google Keep Chrome app in February 2021. The app is being moved to Google Keep on the Web, from where it can still be accessed. Access to Keep on the Chrome OS lock screen will also not be available anymore.
Source