No problem at all, glad to be of help.

First, I was able to reproduce the bug, though in a weird way.

1) I've googled up this ticket https://www.dreamwidth.org/support/see_request?id=41787, and the https://www.dreamwidth.org/inbox/?view=sitenotices link did the trick for me (see screenshot: https://pritkiy-kaban.dreamwidth.org/file/25035.jpg).

2) The interesting part is that now, https://www.dreamwidth.org/ is displayed properly, while https://www.dreamwidth.org/inbox is not. I was able to reproduce it in Opera and FF.

3) Under FF Network tool, headers are slightly different.
The Home page (Cyrillic is properly displayed) is as follows: https://pritkiy-kaban.dreamwidth.org/file/25451.jpg
The Inbox page (Cyrillic appears garbled) is as follows: https://pritkiy-kaban.dreamwidth.org/file/25190.jpg


Here are some examples of garbled characters:

Ex.1)
Grabled text: Нет. В т.ч. через встроенный VPN Оперы.
Proper text: Нет. В т.ч. через встроенный VPN Оперы.

Ex.2)
Grabled text: Технический вопрос по DW
Proper text: ТЕХНИЧЕСКИЙ ВОПРОС ПО DW