Tvheadend

Hi.
Tvheadend runs from a container, the image is taken from linuxserver/tvheadend. To get the epg, I use my own grabber (tv_grab_my). I added the grabber as follows, mount the file into the container -v /path/to/tv_grab_my:/usr/bin/tv_grab_my. When I connect to the container, I find the grabber file in /usr/bin. Also, tv_find_grabbers finds my tv_grab_my. But the problem is that in the webui, in the EPG Grabber Modules section, my grabber is not displayed and so I cannot enable it. What do I need to do to activate the module?