The authors do not implement an S3 method dispatch of the generic function spatstat.geom::unmark() to a ppplist, despite the existence of the S3 method dispatch spatstat.geom::unmark.splitppp() that is de facto deprecated (email from Dr. Baddeley, 2025-10-05).
Workaround: unmark a ppplist
spatstat.data::btb.extra |> spatstat.geom::solapply(FUN = spatstat.geom::unmark.ppp)# List of point patterns# # full:# Planar point pattern: 919 points# window: polygonal boundary# enclosing rectangle: [133.5147, 246.0193] x [10.88514, 118.7298] km# # standard:# Planar point pattern: 873 points# window: polygonal boundary# enclosing rectangle: [133.5147, 246.0193] x [10.88514, 118.7298] km