I have three or four Edit fields. Chaning their fonts will make these fields to repositioned because each line has changed its dimension. But the anomaly is if the focus is not at the first field, then the focused field will not be shifted. This makes other fields to be shifted to a new position relative to the focused field. This can cause the first field to be shifted up and down out of its first top position.

To fix this, right before changing fonts, I put the command TopOfDisplay(), then change fonts, then put the focus back to the current field.