@Mats_Knutsson You could see if WIDO_REVEAL_SIDE is relevant to what you need. Might be worth looking at the GS door / window marker as I think that uses the reveal side to orientate itself. You might even answer your question by temporarily showing the markers?
Apple iMac macOS Monterey / AC25UKI (most recent builds)
I don't think there is anything you can label that will tell you the placement (reveal or external sill) side of a window.
There possibly would be a GDL solution where you could add a symbol with a white pen (so it doesn't print) or have a parameter that turns it on/off, but that would mean altering the script of all the default windows if you use those - and that is not a good idea.
I had thought a window marker might do it but it seems not.
If you 'Flip' window, the marker flips as well, but the reveal side does not alter.
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