Why does pressing return jump to another workbook?

I’m running LibreOffice 6.4 on openSUSE Linux (in KDE), but this has been plaguing me through several versions of 6.3.

Scenario: I have multiple workbooks open. I am editing a cell in one, and I hit the “return” key to conclude editing.

It closes the editor, but instead of jumping to the next cell, the screen jumps to another open workbook (sometimes on another virtual desktop).

This seems bizarre behaviour - has anybody come across it? Or knows how to turn it off?

Using the same configuration like you - but never faced something like this. Did you perform some KDE tweaks? (From my point of view the window manager [KDE] is responsible for switching windows). Have you ever reset your KDE configuration?

Not for a while, but I’m considering that as the nuclear option (as I’m sure I’ll spend forever trying to identify all the settings I want to preserve).

Even weirder, it’s intermittent - sometimes it works fine and does what you’d expect, and sometimes jumps to another window…