The cursor should never be on the right edge of a dashed-blue-box.
To reproduce this, select the first 'Sums' symbol, and then click to the right of it.
When you click sum, it creates a box for the sum. The box is supposed to contain whatever comes inside the Sum boundary. But what would you do to type outside of the sum equation?? There is open space both on right and left of the equation and the user is allowed to type in those places. For examples look at the attachment.
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When you click sum, it creates a box for the sum. The box is supposed to contain whatever comes inside the Sum boundary. But what would you do to type outside of the sum equation?? There is open space both on right and left of the equation and the user is allowed to type in those places. For examples look at the attachment.