Relationship between FilterAura and button?

[siweia]

Before oUF 11, I use customFilter to consolidate all bolster in mythic plus.

The code is what I did before, but in oUF 11, button no longer accessable in FilterAura.

local function PreUpdate(element)
    element.bolster = 0
    element.bolsterIndex = nil
end
 
local function CustomFilter(element, unit, button, name, _, _, _, _, _, _, _, _, spellID)
    if name and spellID == 209859 then
        element.bolster = element.bolster + 1
        if not element.bolsterIndex then
            element.bolsterIndex = button
            return true
        end
    end
end
 
local function PostUpdate(element)
    local button = element.bolsterIndex
    if button then
        button.Count:SetText(element.bolster)
    end
end