Hello List, In "The LaTeX3 Sources" document it says (on p. 296, Released 2018-12-12): "Older versions of expl3 divided up primitives by “source”: that becomes very tricky with multiple parallel engine developments, so has been dropped. To cover the transition, we provide the older names here for a limited period (until the end of019)." Does this mean one should avoid using functions such as "\etex_iffontchar:D"? If yes, are there any alternative to such commands? Furthermore, in "The expl3 package and LaTeX3 programming" document it says (on page 7, Released 2018-12-12): "D This means: Do not use. This special case is used for TEX primitives. Programmers outside the kernel team should not use these functions!" Again, which function should a programmer who is not a member of kernel team use instead of "\etex_iffontchar:D"? Thanks, Tisha