In hopes that restarting KDE would resolve my issue, I logged out and logged back in.
On Login, I saw a brief Notification popup that Reported “Layout Set to Columns”.
So looking in Personal Settings - Shortcuts and Gestures-Global Keyboard Shortcuts-KWin,
I observed that “Meta+PgDown” is the “Next Layout” shortcut.
Meta+PgDown put me back in “Floating” layout, reported in another Notification message, which seems to be what I was looking for.
I found no other way to reset this
There is a dropdown menu in Personal Settings-Window Behavior-Window Behavior-Advanced for Default Tiling Layout.
I had set that to Floating (from Columns), which was not effective, but perhaps needed to restart KDE again (logout-login) for that setting to work; I don’t think I tried that.
Or, after reading THIS ITEM it seems possible I accidentally turned on Tiling with an alt+shift+F11 fatfinger.
In looking at another 12.2 machine (my laptop), I see that tiling is OFF, I’ll assume that is the default setup.
Not clear to me yet what the difference is between Tiling=Off and Tiling=ON with Default Tiling Layout=Floating
>
>Resolved!
>
>In hopes that restarting KDE would resolve my issue, I logged out and
>logged back in.
>
>On Login, I saw a brief Notification popup that Reported “Layout Set to
>Columns”.
>
>So looking in Personal Settings - Shortcuts and Gestures-Global
>Keyboard Shortcuts-KWin,
>I observed that “Meta+PgDown” is the “Next Layout” shortcut.
>
>Meta+PgDown put me back in “Floating” layout, reported in another
>Notification message, which seems to be what I was looking for.
>
>I found no other way to reset this
>There is a dropdown menu in Personal Settings-Window Behavior-Window
>Behavior-Advanced for Default Tiling Layout.
>I had set that to Floating (from Columns), which was not effective, but
>perhaps needed to restart KDE again (logout-login) for that setting to
>work; I don’t think I tried that.
>
>Or, after reading ‘THIS ITEM’ (http://tinyurl.com/bsdxasj) it seems
>possible I accidentally turned on Tiling with an alt+shift+F11
>fatfinger.
>
>In looking at another 12.2 machine (my laptop), I see that tiling is
>OFF, I’ll assume that is the default setup.
>Not clear to me yet what the difference is between Tiling=Off and
>Tiling=ON with Default Tiling Layout=Floating