"Key sequence will not work in editor." on keybind that previously worked

I have had the "GotoNextCharacter" command bound to Shift+Space for the last couple years I have been using Qt Creator. Today, upon updating to Qt Creator 4.12.4 (from 4.12.2, if my memory serves me correctly), that bind has quit working. I checked "Environment -> Keyboard" in Options to make sure that it was still bound, and it is, but underneath the key sequence is a message stating that the "Key sequence will not work in editor. Does anybody happen to know why this sequence no longer works?