Unread conversations count bug?

[nocte]

I have installed this addon on a test board and found that I see a 1 counter for unread messages in the inbox, if there are not any:

Once I receive a message (which is unread), the 1 disappears

Is this a bug or am I doing anything wrong?

Latest XF and addon versions.

P.S. from my testing so far, it seems unread and read values are kind of flipped.

 

[Xon]

What the heck.

I'll look into it, I suspect there is a sign flipped somewhere as I had redone how these counters had been incremented