breeze-cursor-theme software package provides Default Plasma cursor theme., you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install breeze-cursor-theme
breeze-cursor-theme is installed in your system.
Make ensure the breeze-cursor-theme package were installed using the commands given below,
$ sudo dpkg-query -l | grep breeze-cursor-theme *
You will get with breeze-cursor-theme package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | KDE |
| Package | breeze-cursor-theme |
| Version | 4:5.8.2-1 |
| Description | Default Plasma cursor theme. |
| Sub Section | KDE |