New warning (or at least I only noticed it now)

[Pavel Sanda]

On Mon, Nov 21, 2022 at 10:09:15AM +0100, Jean-Marc Lasgouttes wrote:
> I cannot really understand what the destroyed temporary is. 

Don't we create and return temp at GuiApplication.cpp:3695 ?
If you look above at theFontLoader (GuiApplication.cpp 3689)
we do similar logic but we reserve font_loader_ for the construct. 
Or we could stop use & so copy happens.

Pavel