like @Steef66 (many thanks btw) already answeredMay I ask what is CLOU ? it is apparently some type of finish or oil ?
it is the CLOU sanding primer - the german term is CLOU Schnellschleifgrundierung
@Jeronimo was (I think) the first one who mentioned it here in the forum and in the meantime several others are using it on a regular basis.
The wood is slightly darkening after the treatment with Clou, a little bit dull surface, you can glue parts afterwards, also painting with Ecoline is no problem.
Since I got the tipp with Clou I am not oiling any more