This is a random occurrence, but I have experienced it at least 6 times since the Resin Update. Sometimes, when a new duplicant is available, clicking on the "Choose Blueprint" button results in the game freezing with only the "Blueprint selecting music" playing. The game must be terminated and restarted at the last save.
Click on "Choose Blueprint" when a new duplicant is available. This is completely random, as far as I can tell.