Finn, (and others of course)
what to you make out of the following?
In 7.13.2 alignment-baseline is defined as having the values:
auto | baseline | before-edge | text-before-edge | middle | central |
after-edge | text-after-edge | ideographic | alphabetic | hanging |
mathematical | inherit
But further below in the text where it says "Values have the following
meanings:" we have at the end explanations for the values:
top, bottom, text-top, and text-bottom, which according to the
definition above are not valid values for this property.