GPOS in sequence with zero width joiner?

pos A' <-100 0 -200 0> Z;

So does this:

pos A' <-100 0 -200 0> B Z;

But this doesn't:

pos A' <-100 0 -200 0> uni200D Z;

It looks like Chrome ignores the zero width joiner (uni200D) so the sequence A‍B still works. But Edge chokes on this.

It's similar to this thread, except there Edge needed the zero width joiner to be present, while here it breaks when it is present.

Any idea how to position a sequence that has a zwj in it?