Help with TabManager & PlaceholderAPI?

I’m trying to get the TabManager to show custom javascript placeholder on the group suffix. What I want to do is to pass each nickname in the TAB list to a JavaScript placeholder as an argument. Problem is, that the placeholder “works” but it doesn’t replace it, only appends to it.

What I tried:

What I expected:
return true or false depending if that player is AFK or not.

What I got:

So it replaces the nickname as it should, but then it appends the script output to the placeholder instead of replacing it fully.

Also I noticed that the %player_displayname% shows that player who is currently looking the TAB list, not the player the list is “printing” at the moment. So it will always check only “your” nickname for every player in the list.

I’ve been trying to show suffix which indicates if player is AFK or not, but it seems not to be possible…