Store a value associated with a window?

[LyLerK]

Thanks for the functions, 1 problem.
for FINDPROPDATA, I am getting unknown identifier. It is not appearing in purple/pink. Am I missing a file?


I figured out a solution I am pretty happy with using TagWindow + RegWinPos but your solution appears to be exactly what I was previously looking for.

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Edit: Code removed, contained error
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