Visibility collapse
Spec
Setting a row to visibility:collapse changes table height but not width.
Here, the spanning cell is the only cell in its row.
B B B B B |
| aaaa |
| bbbb |
| cccc |
| dddd |
Bottom table is identical to top except second row has been collapsed.
The spanning cell's height shrinks and is clipped.
B B B B B |
| aaaa |
| bbbb |
| cccc |
| dddd |
This text should not intersect with the table.