Multiple Value Kerning Groups

Hi all, I’ve tried to look for documentation on this but can’t seem to find what I’m looking for. In the Kerning help page, they mention Group Kerning but not in a way that answers my question below:

When the cursor is placed between two characters, two boxes appear in the grey box for ‘Kerning Group’ on the left side. Each one has a lock on it. Now I understand the general principle of Kerning Groups and exceptions - what I don’t understand is why the left hand side has two input boxes for Kerning Groups, with two locks and why the right hand side only has one?

What does this mean?

Thanks in advance!

On the left is the lock to mark the left glyph as a kerning exception and its group name (e.g. ‘t’) and on the right is the kerning value between the two glyphs (e.g. ‘-5’), the lock to mark the right glyph as an exception, and its group name (e.g. ‘o’).

Thank you! So in a nutshell, the left and right kerning group for the active character is in the 2nd and 3rd (middle and far right) slots and the kerning group for the character to the left of the active character is in the 1st (far left) slot.

I think you got it. For reference, here is a diagram with the different parts of the Info box: