I noticed you posted this as an issue in the r-utf8 gh repo as well. In general, if you do cross-post (which is discouraged in some cases, though I was gonna suggest you open up an issue anyhow in this one), please be sure to link to the other post, and update if you get an answer. That way, no one wastes time trying to help you with a problem you've already solved. (I know that isn't the case here, but FFR).