/usr/share/audacious/Skins/Osmosis/pledit.txt is in audacious-plugins-data 3.9-1build2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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Normal=#a6c1df
Current=#eeeeee
NormalBG=#000000
SelectedBG=#666666
Font=Helvetica
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