This seems to be when the calculation causes the display to have to scroll.
Example,
Using calculator with the Basic view and not stretched, enter 10000+10000+10000+10000. The view incorrectly displays the result. In some calculations is appears as if the figure has completely vanished as noted above although I suspect the value is 'off screen' to the right enough to be completely hidden. Re-sizing the window in any way seems to re-validate the layout and correctly display the components and values.
This seems to be when the calculation causes the display to have to scroll.
Example,
Using calculator with the Basic view and not stretched, enter 10000+10000+ 10000+10000. The view incorrectly displays the result. In some calculations is appears as if the figure has completely vanished as noted above although I suspect the value is 'off screen' to the right enough to be completely hidden. Re-sizing the window in any way seems to re-validate the layout and correctly display the components and values.