Disabling the key combination to change keyboard layout

Question

I use a standard English (UK) keyboard layout for almost all my work. I very occasionally use a Greek keyboard layout, so I have this set as an alternative layout and the wonderful dropdown menu appears next to the mail icon.

However, every now and then it seems to change of its own accord. Clearly there's a key combination that I've accidentally triggered, but I haven't been able to work out what it is.

I use the layout so rarely that I don't want a keyboard shortcut: how can I get rid of this shortcut?

Answer 1

If you open the keyboard configuration dialog, there is an "Options…" button at the bottom right. One of those options allows you to select a key combo to change keyboard layouts; you want to deselect all (or choose one you will never activate accidentally).