The Kunena team has announce the arrival of Kunena 6.2.5 [K 6.2.5] which is now available for download as a native Joomla extension for J! 4.3.x/4.4.x/5.0.x. This version addresses most of the issues that were discovered in K 6.1 / K 6.2 and issues discovered during the last development stages of K 6.2
They are on this site too and they dont link to anywhere useful, on my site help is disabled and they still link.. Here it is enabled and goes to a useless help page.
I wouldn't call it a bug. The help page for the boardcode link probably doesn't exist any longer. At the very least the link is wrong. Something the devs might have overlooked. (Did it ever work? Even in FireBoard?)
The video link inserts video tags like it's supposed to.