Firewall Rules block by range

Maybe I have missed it, but I have a need to be able to configure firewall rules to block inbound and outbound based on a range. Right now the only options are to block by Any address, single address, or network. My issue is I need to block a specific range of addresses, not an entire subnet. There are other areas that allow ranges, but the firewall rules do not.

Please advise if anyone knows a way to do this, if not, please consider adding this feature. My previous firewall had this capability as have others that I have worked with.

This is a great idea for future firmware releases. Thank you for the suggestion.