This package is obsolete; do not use in new documents. It will do nothing in LaTeX formats after 2015/01/01 as the fixes that it implements were incorporated into the fixltx2e package, which is itself obsolete as since the 2015/01/01 release these fixes are in the LaTeX format itself.

Fix mark handling so that \firstmark is taken from the first column if that column has any marks at all; keep two column floats like figure* in sequence with single column floats like figure.