Hello, please tell me to whom to write if I have a suggestion to development Okular?
For the module FB2 small refinement to the tips to the references to footnotes, finding does footnote. I downloaded the source code itself and has already done so.
I can send the modified files.

I would suggest the okular-devel mailing list https://mail.kde.org/mailman/listinfo/okular-devel

i was try.
any mail to okular-devel@kde.org
make me answer from my mailer mailer-daemon@yandex.ru
--
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
--
i also try ask in irc, no body home.

to post on the mailing list you must first subscribe:

To subscribe to Okular-devel please send an email to okular-devel-request@kde.org with the subject "subscribe"

i was subscribe.
i try subscribe again? same error. it-s new/ first time subscribe was succes.

in error
-----------
This is the mail system at host yandex.ru.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

Please, do not reply to this message.


<okular-devel-request@kde.org>: host postbox.kde.org[46.4.96.248] said: 554
5.7.1 Mail has been rejected as SPAM (8.153) (in reply to end of DATA
command)
-----------

It seems I was mistaken for a spammer

wait and try the irc channel #okular again

I have investigated your issue with the KDE.org spam filters - it seems that the Yandex webmail client you are using is sending terribly malformed email (not helping matters is that the servers hosting their webmail client have been listed as abusable hosts).

Unfortunately there is little I can do as the rules it is tripping are legitimate. All I can suggest is using a different mail client (such as Thunderbird for instance) with your webmail account.