Mozilla Bug 386813 Mozilla Bug 513848 Mozilla Bug 761853

column1 column2 column3
row1 cell1 cell2
row2 cell3 cell4
row3 cell5 cell6
grid-rowgroups-col1 grid-rowgroups-col2 grid-rowgroups-col3
grid-rowgroups-row1 grid-rowgroups-cell1 grid-rowgroups-cell2
grid-rowgroups-row2 grid-rowgroups-cell3 grid-rowgroups-cell4
grid-rowgroups-row3 grid-rowgroups-cell5 grid-rowgroups-cell6

header1 | header2

cell1 | cell2