Say you have two language layouts: French and German. You set a shortcut to switch layouts, and the shortcut is Alt+Space. If the current language is French and you press Alt+Space, it switches properly to the next language, German. However, pressing the combination again does not switch back to French. Simply, it stops working. It works again when you manually go back to French.
This occurs in several flavors I've interacted with: I tried this on Kubuntu 20.10, Xubuntu XFCE 20.04, and Lubuntu 20.04 LXQT. For these three I used the latest most popular releases.
How do I repair this problem so I can continuously switch languages whenever I press Alt+Space?