Describe the bug

After logging in with SDDM I see the following window:

Every time. This is annoying and should not happen. Previously, no manual intervention was necessary. This is a regression in 20.09.

This is like #83095, but for 20.09 this time.

To Reproduce
Steps to reproduce the behavior:

1. Enable NetworkManager, SDDM and Plasma.
2. Store Wi-Fi password in KDE Wallet (store password for this user only - encrypted).
3. Set KDE Wallet password to password used to log in.
4. Log out.
5. Observe the above-mentioned window.

Expected behavior

No manual intervention should be necessary.

Notify maintainers

@ttuegel @nyanloutre

Metadata
Please run nix-shell -p nix-info --run "nix-info -m" and paste the result.

• system: "x86_64-linux"
• host os: Linux 5.4.72, NixOS, 20.09.1469.13d0c311e3a (Nightingale)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.3.7
• channels(xfix): ""
• channels(root): "nixos-20.09.1469.13d0c311e3a, home-manager-20.09"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
# a list of nixos modules affected by the problem
module: plasma5