Confirmed it's something in the 1099-B page or backend. I just filed for my Aunt who has no 1099-B, only a 1099-R, and while the same page came up under review, to review the 1099-R and make a correction, the page did not hang while rendering the form image, so the problem is definitely with either the code for the 1099-B page or the backend to parse the data for review. Again, it seems to be tied to the last row in the form as if I delete the last row, the error occurs for the row immediately before, indicating that the problem will always be with the last row in the dataset.
