TL;DR: A KWin script to tile windows in a way similar to KWin < 6.3. You can find it at https://github.com/pedroarthur/kwin-liv-tiler
The 6.3 release ships with significant changes in the Quick Tile functionality. I didn’t like them. =P As much as I find it funny to see the windows behave like a worm when you quickly tile them from the rightmost screen to the leftmost (it is amusing indeed), the new implementation requires more keystrokes and has some annoying inconsistencies.
Since it would take a long, long time to adapt, I took a couple of hours to rewrite the old quick tiling using the KWin scripting interfaces. I hope you enjoy it.