Description:
After a recent system update, Dolphin file manager has ceased to function properly outside of KDE environments. Attempting to open any file leads to the default application assignment window popping up; however, this window is now showing empty without listing any applications, as if all application associations have disappeared.

This issue became noticeable with the introduction of Plasma 6, at which point I could resolve the problem by manually starting the /bin/kded6 service, allowing default applications and xdg-open to operate normally. However, following the latest update, this workaround is no longer effective, and the default application window remains empty, leaving no possibility to launch any files.

Impact:
This is a critical issue as it completely hinders the functionality of Dolphin in non-KDE desktop environments, affecting productivity and system usability.

Steps to reproduce:

1. Update the system including Dolphin and KDE components on arch.
2. Open Dolphin in a non-KDE environment.
3. Try to open any file.
4. Observe that the default application assignment window opens but contains no applications.

Expected behavior:
Files should open with their associated default applications as defined in the system settings or fall back to using xdg-open.

Actual behavior:
The default application window is empty, and no files can be opened directly from Dolphin.

System information:
    KDE version: Plasma 6
    Dolphin version: 24.02.2
    Operating System: Arch Linux

Severity: Critical

Note:
This issue does not occur within KDE environments, only when using Dolphin in other desktop environments.