There are a couple of reasons not to worry about this upgrade: A. 3 -> 4 required very very significant changes. 4 -> 5 and now 5 -> 6 are nowhere near that.

There are a couple of reasons not to worry about this upgrade: A. 3 -> 4 required very very significant changes. 4 -> 5 and now 5 -> 6 are nowhere near that. B. KDE really learnt their lesson on this and they are very careful not to create anything similar to that. Thus, not big rewrite/changes like 3 -> 4 are in the works. This is just to get the whole project going with Qt 6 which isn't that much different from Qt 5. Edit: Disclaimer, I used to be a very minor contributor to KDE around 3 -> 4 time.