URL Filter is designed or limited to work with just two directory stages of blocklists tree .
One main “blocklist name of category” and one stage under there the subdirectory or subdirectories as group .
So the scrip work path for (searching and reading) for domains.db files, is not limited in path length;
But the script to write modifications done to an blocklist is limited in path length, to a tree of just two directories path .
Same limit is present when exporting an loaded blocklist …
The script for modification and the script for export, do not consider more longer file path for file domains and file domains.db paths .
Just an example for understanding :
/var/ipfire/urlfilter/blacklists/automobile/boats (read file domains.db works, write changes to file domains.db works)
/var/ipfire/urlfilter/blacklists/m/automobile/boats (read domains.db works, write changes to domains.db not works)
/var/ipfire/urlfilter/blacklists/s/automobile/boats (read domains.db works, write changes to domains.db not works)
/var/ipfire/urlfilter/blacklists/u/automobile/boats (read domains.db works, write changes to domains.db not works)
/var/ipfire/urlfilter/blacklists/c/automobile/boats (read domains.db works, write changes to domains.db not works)
Since IPCop and IPFire core 99 I use alternative download custom blocklist .
The maintainers “parent group” who offer the download blocklist, include there the Shalla “s”, Univ.-Touluse “u”, MESD “m” and other Custom “c” domains and URL paths blocklist for private home use .
This was tested and was working for long years, I cannot remember having any issues, but I musts confess that it was long years ago when last time I had made changes manually to the blocklists .
So it seems there was done some script changes to IPFire URL Filter at last … not sure I think maybe since core 122 or core 130 ??
At now I think it is just Shalla Secure Service who use grouping blocklists …
Interest is, if the IPFire developers are willing devout make modifications to the URL Filter script, to allow longer path of blocklists directory tree .
Maybe as future proof of flexibility using other alternative blocklist maintainers ?
I still have two too inexperienced ladies at home and must avoid deleting the whole internet …
For my future use, I will use my NAS at IPFire DMZ, to download manually path modified blocklists by direct renaming, to avoid getting category duplicate over write and not to run into this path matter again .