HTMLTableElement's insertRow() method
The first three test whether HTMLTableElement's insertRow() method can add an implicit tbody into a table without one, to hold the inserted row.

The first tests an empty table

The second tests a table with text contents.

The third tests a table with only a form element inside.

The next four test the method on typical cases.

The first tests a table with only a thead

The second tests a table with only a tbody

The third tests a table with only a tfoot

The fourth tests a table with a few rows and cells

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