@Hannsek I am not sure if this issue is relevant
The behavior depends on the layout model:

• model_tr does not have this issue. However, the time period of the last number being is bounded by the next button press (not a time period).
  

• model_tt and model_mercury do not show the last digit but rather show an entire PIN when the area with pin dots is touched. However, there is nothing that informs the user about this feature.
  
  The only way to theoretically display this information is in the PIN dots are before the first digit is inserted.

@bieleluk the goal here is to unify the behavior across models as much as possible. That means the following:

model_t and mercury

1. after entering a digit, keep it revealed for a short period of time - e.g. a timeout of 1 second
2. reveal the whole PIN when the input area is touched (this is done)

model_r

1. here, that's a question, I didn't know the digit is revealed until you move the carousel. I think a good modification would be to hide the digit after the "shuffle" of the carousel is finished. The resulting behavior would be similar to model_t and mercury. However, the implementation might be shared for this and the "Show" button so splitting it might be a little bit difficult.
2. reveal the whole PIN when the "Show" button is pressed until you move the carousel (this is done)

Summary

IMHO, the best effort is to newly implement the point 1. for model_t and model_mercury and keep model_r unchanged.

We already have a timeout for SLIP39 keyboard IIRC. Let's use the same behaviour for all core models for PIN input. If not implementing this for model_tr is easier, let's not implement it for model_tr.

model_tt and model_mercury do not show the last digit but rather show an entire PIN when the area with pin dots is touched. However, there is nothing that informs the user about this feature.

This is not relevant to this issue.