"1. If any flexbox items in the flexbox's first line (after flex-order reordering) are baseline-aligned, use that. 2. Otherwise, if it has at least one item, and the baseline of its first item (after flex-order reordering) is parallel to the main axis, use that. 3. Otherwise, it's the after inner edge. Flexbox items have the computed value of 'display' changed by the table in CSS2.1 Chapter 9.7. In particular, inline-block now becomes block."
*** This bug has been marked as a duplicate of bug 95889 ***