Adding a field for personal note on block list and allow list

Hi,

I have created a lot of custom allow and block list items but when I look back I find it hard to know why and also when I added those to the lists. 
It would be very helpful if you could add one optional column that a user like me could add some comments about why a certain domain was blocked

 for example

 blocked domain

ads.xyz.com

optional field: added this domain when I spotted this as an ad on my web mail app.