Summary

Be able to use a single short cut to cycle all visible windows into the master area, in the same way that Alt+Tab can be used repeatedly to focus any window.

A clear and concise description of what you want to happen

Currently we have 3 ways to move a window from the stack area to the master area: focus a different window via Meta+HJKL and Meta+Return, use Alt+Tab then Meta+Return, or use the mouse to drag it into the master area, swapping positions with the current occupant of the master area.

This direct selection of master occupancy requires the user to think 'where is the window that I want to focus now', then carry out the spatial Meta+HJKL focus move to the desired new master, then Meta+Enter. Or use the sequence of Alt+Tab, Meta+Enter

KWin's window 'tab order' (the stack or circular list of windows accessed via Alt+Tab) provides a good candidate for a 'Push Next Window to Master' action.

Use case: Billy is a coder and wants to flip between having StackOverflow and a Konsole with Vim in the master area. He also has a media player and a status monitor in the stack area. While StackOverflow is master, he presses a shortcut and the previous master window (Konsole) is made master again. He presses the same shortcut a second time and StackOverflow and Konsole change places, Konsole becoming master and StackOverflow going to the stack.

|       |[Konsole]
|   SO  |[ Music ]
|       |[Status ]

"Next Master"

|       |[  SO   ]
|Konsole|[ Music ]
|       |[Status ]

"Next Master"

|       |[Konsole]
|   SO  |[ Music ]
|       |[Status ]

The stack layout remains the same, this is not the same as rotating the layout.

A clear and concise description of any alternative solutions or features you've considered.

Perhaps this could be combined with Alt+Tab, where the focused window is always master. I think this might be too intrusive though.

Additional info

The default tab order would work like Alt+Tab's tab order, a stack structure where the selected item is popped from the stack and pushed on top of the previous master occupant. It may even be the same stack!