In all honesty, you'd probably be better off in the long run saving the FITS files and processing in a third party app such as Siril (freeware) or PixInsight (not free). You could then find the FITS files that have the star trails, delete these files, and restack thus eliminating the trails in your master FITS file.
PixInsight has a feature called "Blinking" (I think thats the name) where it quickly display your list of FITS files and you can more easily identify the bad FITS files. Not sure if Siril has an equivalent.
The Seestar also has a restacking capability (DSS) that you can use but you'd still need to identify the bad FITS files.
In my opinion, i doubt your feature request will ever be implemented by Seestar.