How can I make SwiftKey keyboard show up when replying to messages in lock screen? I have SwiftKey keyboard installed on my iPhone (5, iOS 11).

When I am in normal apps (e.g. Google Hangouts), it is possible to use it.

However, when I hit "Reply" to Hangouts messages on Lock Screen (which doesn't open full app), it only lets me use built in iOS keyboard, not Swift. I think the same happens when filling in password.

How can I have SwiftKey used as a keyboard 100% of time?
If you have Touch ID or Face ID, make sure to unlock your phone with your finger/face before tapping the reply button.

Otherwise the best shortcut there is, is to unlock your phone with your passcode and then drag down notification center from the top of the screen. Then press the reply button from there.