Forum interface is reset to Russian every time after login

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en

ну давайте попробуем создать Форум топик ен.

Well, half-reset, other half is still in English.
Goto forum.acronis.com; interface is in English, ok. Login, it sets interface language to Russian. Ok, I go to account->preferences, set English there, all is in English now, then I log out. After the next login it is again half in Russian half in English.
ps - I see no point of having interface translated in the forum that is officially English. Maybe for KB where translated content may appear some time later.