Hello. I encountered one nasty bug in Firefox: When I create a table with two columns, where the first column has borders and two cells, while the second column has no borders and is set to rowspan=2, the result is ugly. See how it looks:
http://primerecords.dk/Wikipedia/border-collapse.html
Both corners in the second column are broken. I consulted my friends at Wikipedia about this problem. They confirmed that this problem is only in Firefox; in other browsers, the border corners are displayed correctly.
For completeness, I'm also including the wikicode here:
{| style="border-collapse:collapse"
| style="border:8px solid" | A
| rowspan=2 | C
|-
| style="border:8px solid" | B
|}
And when you edit cell "C" with the following style, the result is absolutely crazy:
| rowspan=2 style="border:2px solid" | C
