[Taudier]

this code, change 100 and 20 by what you want :

MainMenuBar:SetMovable(true)
MainMenuBar:SetUserPlaced(true)

CreateFrame("frame", nil, nil, "SecureHandlerBaseTemplate" ):WrapScript(ActionButton1, "OnShow", [[
local MainMenuBarArtFrame = self:GetParent()
local MainMenuBar = MainMenuBarArtFrame:GetParent()
local UIParent = MainMenuBar:GetParent()
MainMenuBar:SetPoint("BOTTOM", UIParent, "BOTTOM",100, 20)
]])

MainMenuBar:HookScript("OnEvent", function(self, event)
	if event == "PLAYER_ENTERING_WORLD" and not InCombatLockdown() then
		self:SetPoint("BOTTOM", UIParent, "BOTTOM", 100, 20)
	end
end)

if you change the option to show/hide the bottom right bar you have to reloadui