Would be happy to see a patch (although it also needs to backfill some tests too).

One workaround would be something like:

Or you could use another zipper library like hara.zip which doesn't have remove, but works with delete-right:

Comment made by: chbrown

4+ years later, I also ran into this.

Is there a workaround? I.e., is there a way to remove elements from singleton branches?

Also the docstring for zipper should probably be updated to indicate that the children parameter can be nil.