I thought maybe there is something where you can connect a cable at both ends and something narrow in the middle under the door. Such a thing exists, if I remember correctly, for SAT.
Is available for SAT, it is for windows or balcony doors. You don't seriously want something like that for interior doors, do you?!? It's already crap for SAT, and for network there is no such thing anyway.
Yep, I'll do it on my own :). I just haven’t done the project over several floors yet, until now I’ve always laid it under the carpet all the way behind the cabinet, and that always works quite well.