Ahoy folks !
Instead of setting up in Haiku a Russian keyboard as well, I was curious if I even find an online service to do that.
I know - there is an On-screen keyboard in Haiku and possibly the language could be / should be selectable … but some ‘solutions’ are not easy-peasy … and as I had not use Haiku as a polyglot user, just as I am not a real polyglot … 
… I do not know exactly how it works ( Later I may check it out )
So I wanted a quick, available, not configuration dependant, jetlaunch efficiency solution … especially as I’m a lazy-easy-going man in a positive meaning as well …
I found Typeit (it is its homepage link) , as a Russian Letter typing online helper.
It is available for more languages,like my native, Hungarian, containing the differencies only for Latin charset in this case.
Of course, languages which use different characters, alphabets also available and usable.
I would share it for those, who need a workaround if shit happens and / or
your language in Terminal or in an app needed to have your native characters, but actual OS/app cannot serve it, or their actual status require you have an alternative or a workaround to complete something … and of course you have access to the net and working reliably to use this online service on your device.
(Oh yeah, anyway … there are math symbols as well, if you would type them → Math symbols )
I hope it can help you out in your tight/lifesaver situations –
Anyhow – me myself I found it useful --, so I bookmarked in Webpositive !..
Kind regards,
EDIT #01:
(hoping : later it would work in it - it turned out I used it really in Falkon :((, I just bookmarked in Web+ as I gather such services there … this way I remembered os it works in it …
Now as I tested : it had not written anything into input field - clicking on letters’ buttons.
I removed works in Web+ from the title)
EDIT #02 :
Ticket #19071
was created to be investigated and if possible working as expected in Web+ too.