Huh, tbh I’ve never given KDE a real try. I used it way back in the day on OpenSUSE because I wanted a windows experience but that was when I was still playing around with Linux. I’ve never used it full time. My first full time DE was cinnamon and eventually I decided I wanted something radically different and so went to gnome 3 and never really considered KDE as radically different from anything I had used before.
Linux remaps 0.0.0.0 to 127.0.0.1 when you attempt to use it as an address…does the same thing for :: remapping it to ::1