IBus 1.5.25 will use Ctrl-period shortcut key to toggle Emoji typing on-off while the previous shortcut key was Ctrl-Shift-e shorcut to follow GNOME desktop. and the ibus-anthy's circle_kana_mode could prevents the emoji typing.

MS-Windows uses Super-period but GNOME uses Ctrl-period.
ibus-anthy's shortcut keys follow MS-IME but this shorcut key will be an exception.