Our Esperanto club is interested in providing as extensive as possible language support for Esperanto in a various tools. I’ve installed the Language Tool extension for LibreOffice Writer, but there appears to be no spell checker. I would like to get our group involved with developing such an Esperanto spell check dictionary for LibreOffice. The group is heavily weighted with engineers and programmers, both active and retired, and I’m sure we could pull it off. Is there any LibreOffice documentation on dictionary creation?
Kelkaj esperantaj vortaroj jam troveblas:
https://extensions.openoffice.org/en/search?query=Esperanto+
Mi havas mian propran vortaron, provos aldoni ĝin morgaŭ.
Bedaŭrinde, la nura dokumenteto, kiun mi konas, malaperis.
Update:
I attach here my own Esperanto spellcheck extension. Originally, it was a work of Sergio Pokrovskij. I converted the dictionary to the Hunspell format and packaged into extension. Change the file name extension to .oxt (I have always wondered why OXT files are not allowed here).
Marek,
Dankon! Mi instalis la literumilon de la ligilo kiun vi havigis kaj ĝi funkciis kun LibreOffice 5.4.5.1. Proksimume kiom da vortoj ĝi entenas? Se vi volas, povus ni helpi vin etendi vian ilon? En la angla “Many hands make for light work” 
-Tim-
continuing in English because the forum rules are to be observed
Marek (assuming that you mean Marek Blahuš) may not be attending this forum, so you should better contact him directly. I guess, the extension page provides a couple of useful links.
And do not answer your own question unless it is a real answer. Make a comment. If you are satisfied with someone’s answer, upvote it and tick the round mark.
Thought I hit the comment button and was surprised that it posted as an answer. Also I thought you, gabix, were Marek…sorry. Again, thanks for the help. So my “answer” above is really a comment to you