I've been using the "nice empty nodes" style from the forest manual for trees for quite a while now. Today I updated the package, and now it throws an error (though the output still seems to work). Minimal example:
\documentclass{article}
\usepackage{forest}
\forestset{
nice empty nodes/.style={
for tree={calign=fixed edge angles},
delay={where content={}{shape=coordinate,for parent={
for children={anchor=north}}}{}}
},
}
\begin{document}
\begin{forest}
[{},nice empty nodes
[b][
[c]
[
[b] [a]
]
]
]
\end{forest}
\end{document}
Error: "Package forest Error: nodewalk stepped to the invalid node; stack: ",tree,tree,parent". \end{forest}"
Anyone got an idea how to fix this?