u/UsefulAGKHelper2023

Google AI Mode helped me to get the solution (for LMDE 7 Gigi based on Debian 13 Trixie):

You can install the complete KDE Plasma 6 desktop environment on LMDE 7 by running the kde-full package installation command in your terminal. [1, 2]

Preparation and Installation Steps

• Update your system: Open your terminal and run sudo apt update && sudo apt upgrade -y to ensure all system packages are current.
• Install the full environment: Run the command sudo apt install kde-full -y to download the entire KDE software suite and applications.
• Configure the display manager: Choose sddm when prompted during installation for the best compatibility and integration with Plasma.
• Reboot your system: Type sudo reboot to restart your machine after the installation finishes.
• Select your session: At the login screen, click the session selection icon and choose Plasma before entering your password. [1, 2, 3, 4, 5]

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