Usually this means something in between steps inside a single piece of software. As in “interstitial ads”, which play, e.g., between levels of a game. In context, I think this means that GP doesn’t want to see something pop up and celebrate in between the steps of requesting a new OTP and actually being able to use it (such as copying it).

(Also, for the record, since I’ve had people argue with or downvote me just for expounding on someone else’s point: this is not an endorsement of GP’s opinion, only an explanation.)

Nobody is conscripting you to use this particular 2FA app. They made it _for_ fun. Not for getting the most users, not for serving the most business use cases, not for being the most secure, and (thank god) not for trying to make a buck. Just for plain ol' simple goal of having fun making something, something which makes them smile, something which doesn't need to be optimal for productivity, something they can share and others who might also smile at the silliness instead of only worry whether or not they can use this for their business's MDM accounts before considering it might just... be fun to have exist.