The Kunena team has announce the arrival of Kunena 6.4.7[K 6.4.7] in stable which is now available for download as a native Joomla extension for J! 5.0.x/5.1.x/5.2.x/5.3.x/5.4.x. This version addresses most of the issues that were discovered in K 6.2 / K 6.3 / K 6.4 and issues discovered during the last development stages of K 6.4
Important note: Go to the Kunena Dashboard after an upgrade so that the Kunena database tables are also updated. This is particularly necessary for major version jumps so that the table changes are adapted.