Maximize Window to screen height in KDE

I am using KDE Plasma on Kubuntu 17.10 and I am searching for a way to make a window fit the height of the screen, preserving its current width and horizontal position.

For example, on Windows, one can drag the top edge of the window to the top of the screen, while resizing, and the window will be resized this way. Double clicking on the top (or bottom) edge also achieves this.

I have a very large monitor and the ability to resize a Window in this way is rather vital. Otherwise, the only alternative is snapping to the left or right half of the screen.

This keyboard route works for me on Kubuntu 16.04 (and on Kubuntu 18.04 in a virtual machine):

System Settings > Shortcuts > Global Shortcuts > KWin > Maximize Window Vertically

Here, I've assigned Ctrl+Meta+V as the keyboard shortcut (where Meta is the Super or Windows key.

This causes the active window, the one in focus, to be maximized vertically, keeping the horizontal dimension and position on the screen unchanged. You can, of course, choose your own shortcut combination.

(Manjaro, Plasma 5.14) You may middle-click the maximize button in order to maximize vertically or right-click it in order to maximize horizontally. These are defined in System Settings -> Window Management -> Window Behavior -> Titlebar Actions -> Maximize Button Actions.