<p>I don't know how official it is with respect to the GTK+ distribution, but I'm using the selector by Alexander Shaduri which officially belongs to a prodget called <a href="https://developer.pidgin.im/wiki/Using%20Pidgin#win32_gtk_theme" rel="nofollow">pidgin</a>. I don't know however to what extend pidgin is officially related to GTK.<br>
I'll copy the themes over to Geany\share\themes, as you suggested.</p>

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