User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.12) Gecko/20080201 Firefox/2.0.0.12 Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.12) Gecko/20080201 Firefox/2.0.0.12 When I create table with border-collpase: collapse. I create 3 columns, using rowspan on 2nd and 3rd. Everyting is OK (screenshot1.png). Now I want border top for every row where is rowspan used, which works but now additional line is create within first rowspan column in rows, which are not first or last (screenshot2.png). All shown in example bug.html (comment/uncomment line: .first_in_group { border-top: 2px solid red; } ) (tested in Firefox 2.0.12 and 3.0). Reproducible: Always Steps to Reproduce: look at detail

The problem is the extra black line inside some of the cells in the third column, right? If so, I can reproduce the bug using Firefox trunk on Mac.

> The problem is the extra black line inside some of the cells in the third column, right? Yes, that is the problem.

I see this on winXP, Fx2, Fx3 and current trunk

border collapse compuation error resulting from a architectural flaw in the computation of the borders, there is only one last corner that we store in the vertical case, while there should be a much as the rowspan cover.

probably a dupe.

(In reply to comment #8) > probably a dupe. bug 322810 or bug 332977 come to mind, new otherwise.

Actually, bug 332740 looks like it got most information on this bug.