Older versions of FileBot (pre-v4.0) were open-source. You can still find the source on GitHub under filebot/filebot . However, these versions are obsolete—they don’t handle modern codecs, x265, or WebDL naming.

How do I activate my license? ... Your license will then be stored in -v data:/data (i.e. named persistent volume data mapped as / filebot-scripts/LICENCE at master - GitHub

: You may find old forks, such as mobeigi/filebot , which are based on version 4.7.9 or 4.8.0 —the last versions before the software became paid. These versions often lack current metadata support and are considered "outdated" by the community.