My first thought was one of the weedy Erigeron.

Possibly Hesperis matronalis basal rosette??? Not many weedy Erigerons in Europe and this doesn't look like any I know.

thanks

I do not think, Erigeron fits. the leaves a really hairy, almost with bristles

there is a lot of Erigeron anuus around, I know that one

Hesperis is probably around

it is kind of mute now, I know, I just thought that it looked very special or distinct for a weedy volunteer

but the Phlox really is a resilient kind, gift from a friend, so I did not want to wait much longer for the NoID to develop and risk the Phlox...

Looks like Dame's Rocket to me.