The soft keyboard changes the height of the screen, because when you enter the User ID , forecast fields are displayed, on the contrary, they are hidden when you enter Password - because passwords have no suggestions.
You need to align the container of the entry area below, so when the size of the viewport changes, the container slides up โ staying aligned from the bottom โ and there is no bounce effect.
In css something like:
.container{ position: absolute: bottom: 0; }
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