Hello everyone, and this will be my first post.
To make a long story short: I have installed Arch Linux, SDDM, Xorg and KDE Plasma (first of all, I don't know much about Linux so it's a miracle I have successfully installed and configured everything).
The problem is the following: not all lines were changed after changing the language through the settings. Also, I changed the locale in /etc/locale.conf.
For example, on one of the screenshots caption is in Russian, but when I open some context menu - it appears to be in English.
The same applies to all applications - they run with English interface, and in their settings are usually "Choose system language".
Before I had Manjaro, and there in the same applications the language was Russian, as well as in the context menus
KDE Plasma ver.: 5.21.3
Kernel ver.: 5.11.11-arch1-1

Screenshots:
https://i.ibb.co/sFSG1Yp/1.png
https://i.ibb.co/DRLHWYM/2.png
https://i.ibb.co/CvqWZ7x/3.png

Okay, now I realize I wrote in the wrong section of the forum.
I apologize and would be grateful if this post could be moved

Post moved. This is due to the translation not (yet) being 100%. Translation of Plasma and KDE software and websites is a volunteer effort, we welcome contributors
If you see differences in the translation between distributions, please take this to the distribution, as they most likely didn't do the packaging correctly.

Eventually I figured out what the problem was.
I had set the system locale in

Code: Select all

locale.conf

, but I had NOT uncommented the same locale in

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locale.gen

and then, in addition, forgot to run

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locale-gen