Laurent, > << currently involved with programming a footnote package, I was trying > to get a clue about just when to insert \color@begingroup and > \color@endgroup >> > > Some years ago, you discussed misfeatures of the TeX 3 > '\mark' mechanism and ideas for fixing it. Are those ideas > adequate for David Kastrup's present purposes? i'm not sure what you are precisely referring with respect to marks at to be honnest, but i doubt it. the problem wih footnotes is that they split apart boxes without a decent way to interact with the mechanism. that is okay if \mark's are concerned (or specials if they simply mark a point in the stream but fails miserably if the special is trying to implement a stack of regions frank