[AnrDaemon]

Originally Posted by Grimsin SetFrameLevel(40) is not valid. that will cause funny issues you need to stick with numbers under 10, 1-9 is best. use setframestrata as another means of setting levels. so setframestrata("LOW") then do setframelevel(1) so on and so forth. in your case you actually want to use setframestrata("HIGH") setframelevel(5) might even need to change high to overlay chatframes maybe in the overlay level.

1. I've removed that already.
2. Valid values for frameLevel - 0-127. (Or is that 1-128?)
3. Own Blizzard ChatFrame#ResizeBottom - 23, check yourself. /framestack
4. Chat frames actually in LOW strata... Well, not a bad idea, i'll try change strata to MEDIUM at least.

What about hovering? Any ideas how it is realized? There are no frame at all (bar UIParent/WorldFrame), yet it detect mouse movement in the old chat tabs position.

EDIT: Works "good enough" for a beginning.

-- Chattabs?
function FCF_SetTabPosition(chatFrame, x)
    local chatTab = _G[chatFrame:GetName() .. "Tab"];
    chatTab:SetPoint("BOTTOMLEFT", chatFrame:GetName() .. "Background", "BOTTOMLEFT", x, -15);
    chatTab:SetFrameStrata("MEDIUM");
    chatTab:SetFrameLevel(1);
end

Now, if anyone have ideas about hovering... how it is even realized? Track mouse on UIParent for boundbox?