Please see thread https://community.ipfire.org/t/can-i-help-progress-version2-of-ipblacklist-addon/6998
@helix has submitted a patch for implementing the ipblocklists as a core item and it is being integrated into the wui.
If you want to see more of the communications beyond the end of that thread then you can look through the dev mailing list https://lists.ipfire.org/pipermail/development/ - sort by subject and look for “ipblacklist V2”