Bug 516068

SUMMARY
After updating to the latest version of Plasma, the new Plasma Login Manager interface (buttons, labels, and session options) is displayed in English, even though the system is configured to use another language (Russian). The interface does not update even after applying regional settings to the login screen via System Settings.

STEPS TO REPRODUCE
1. Open System Settings > Login Screen.
2. Click the "Apply Plasma Settings" button to sync your user configuration with the login manager.
3. Authenticate and wait for the process to finish.
4. Log out or reboot to view the Plasma Login Manager.
5. Observe the language of the UI elements (e.g., "Sleep", "Restart", "Shut Down").

OBSERVED RESULT
The login manager interface remains in English, ignoring the applied Russian language settings.

EXPECTED RESULT
The login manager should respect the synchronized regional settings and display the interface in the selected language (Russian).

SOFTWARE/OS VERSIONS
Operating System: CachyOS Linux 
KDE Plasma Version: 6.5.5
KDE Frameworks Version: 6.23.0
Qt Version: 6.10.2
Kernel Version: 6.19.0-2-cachyos (64-bit)
Graphics Platform: Wayland
Processors: 12 × 11th Gen Intel® Core™ i5-11400H @ 2.70GHz
Memory: 16 ГиБ of RAM (15.3 ГиБ usable)
Graphics Processor 1: NVIDIA GeForce RTX 3060 Laptop GPU
Graphics Processor 2: Intel® UHD Graphics
Manufacturer: HP
Product Name: Victus by HP Laptop