Also agree.
That line is a shadow.
Look carefully,
and you will see the bottom line of trim continuing to left in and beyond the shadow.
If it were the left side of the trim,
there wouldn't be any line on it.
Correct.
They're mistaking
(or maybe on purpose)
a shadow for the trim.
The bottom trim line extends horizontally THROUGH the shadow and continues to the left.
It's another slide.