This command is used to specify the place from which the right edges of a block are measured, when the block is nested within a table or another block.

Normally a nested block’s edges are measured from the inside of the parent cell’s rules after also taking into account any cell padding. Searching back through the hierarchy of parent tables and blocks, if one is found with more than a single column, or one had its number of columns specified explicitly, then setting <?blockabsright=1 will measure the block from the border of that parent’s column edge. This will still be inside any rules of the parent cell but will ignore any of its cell padding. If no conforming parent table/block exists then <?blockabsleft=1> or <?blockabsright=1> will measure directly from the frame column boundary. From these left and right boundaries, the current block margins will then be applied, along with table rules and padding etc., in the normal way.