Why was the target attribute removed from XHTML 1.1?
It wasn't. XHTML 1.0 comes in three versions: strict, transitional, and
frameset. All three of these were deliberately kept as close as
possible to HTML 4.01 as XML would allow. XHTML 1.1 is an updated
version of XHTML 1.0 strict, and no version of HTML strict has ever
included the target attribute. The other two versions, transitional and
frameset, were not updated, because there was nothing to update. If you
want to use the target attribute, use XHTML 1.0 transitional.