/usr/share/audacious/Skins/Classic1.3/skin-classic.hints is in audacious-plugins-data 3.2.1-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | [skin]
skinDescription=The default skin for Audacious. (Classic variant)
mainwinOthertext=1
|