Document whether it is safe to remove a widget from a gtk_container_{foreach,forall} callback
It would be nice if it was documented whether calling gtk_container_remove from the gtk_container_foreach callback is permitted.
If there is such a requirement, then it should also be documented on the GtkContainerClass "forall" vfunc.
I believe it is permitted to remove a widget again (e.g. GtkListBox seems to have code), but am not completely sure.