Custom PC Abilities

[melemkor]

I've searched and googled for answers to what I'm pretty sure is a trivial question... especially since I've found forum posts that suggest other people resolved the question - but even after trying sporadically over days, I haven't had any luck.

I'm creating a PC for Edgewatch, using one of the campaign-specific backgrounds. I found where to add the feats and skills, but now I simply want to add a custom Character Ability (+1 Circumstance bonus to Deception, Diplomacy, ...etc).

I feel like I stumbled across something like this when creating a custom monster, but I am simply not finding it for my PC. I tried searching the "Permanent Added Abilities" table, since that seemed like the natural place for adding a Custom Ability, but obviously I have had no luck. And scanning 5500+ existing abilities hoping for a lucky hit has proved unsuccessful.

So - I want to add a free-form text field to the Character -> Special Abilities tab. How do I accomplish this?

Thanks!