<s>
Nightingale	B-Language
is	O
a	O
discontinued	O
free	B-Application
,	I-Application
open	I-Application
source	I-Application
audio	O
player	O
based	O
on	O
the	O
Songbird	B-Application
media	I-Application
player	I-Application
source	O
code	O
.	O
</s>
<s>
As	O
such	O
,	O
Nightingale	B-Language
's	O
engine	O
is	O
based	O
on	O
the	O
Mozilla	O
XULRunner	B-Language
with	O
libraries	O
such	O
as	O
the	O
GStreamer	B-Language
media	I-Language
framework	I-Language
and	O
libtag	O
providing	O
media	O
tagging	O
and	O
playback	O
support	O
,	O
amongst	O
others	O
.	O
</s>
<s>
Since	O
official	O
support	O
for	O
Linux	B-Application
was	O
dropped	O
by	O
Songbird	B-Application
in	O
April	O
2010	O
,	O
Linux-using	O
members	O
of	O
the	O
Songbird	B-Application
community	O
diverged	O
and	O
created	O
the	O
project	O
.	O
</s>
<s>
By	O
contrast	O
to	O
Songbird	B-Application
,	O
which	O
is	O
primarily	O
licensed	O
under	O
the	O
GPLv2	B-License
but	O
includes	O
artwork	O
that	O
is	O
not	O
freely	O
distributable	O
,	O
Nightingale	B-Language
is	O
free	B-Application
software	I-Application
,	O
licensed	O
under	O
the	O
GPLv2	B-License
,	O
with	O
portions	O
under	O
the	O
MPL	B-License
and	O
BSD	B-Operating_System
licenses	I-Operating_System
.	O
</s>
<s>
Nightingale	B-Language
has	O
not	O
seen	O
a	O
new	O
release	O
since	O
2014	O
and	O
most	O
,	O
if	O
not	O
all	O
,	O
Nightingale	B-Language
developers	O
are	O
no	O
longer	O
actively	O
contributing	O
to	O
its	O
development	O
.	O
</s>
<s>
Multi-platform	O
compatibility	O
with	O
Windows	B-Application
XP	I-Application
,	O
Vista	B-Application
,	O
7	B-Device
,	O
10	B-Operating_System
,	O
Linux	B-Application
and	O
Mac	B-Application
OS	I-Application
X	I-Application
v10.5	I-Application
(	O
x86	O
,	O
x86-64	B-Device
)	O
.	O
</s>
<s>
Users	O
can	O
add	O
features	O
and	O
change	O
functionality	O
in	O
Nightingale	B-Language
by	O
installing	O
extensions	B-Operating_System
.	O
</s>
<s>
Extensions	B-Operating_System
are	O
similar	O
to	O
the	O
Extensions	B-Operating_System
for	O
the	O
Firefox	O
browser	O
and	O
can	O
be	O
easily	O
ported	O
.	O
</s>
<s>
Community	O
coded	O
extensions	B-Operating_System
are	O
available	O
on	O
.	O
</s>
<s>
Skins	O
are	O
referred	O
to	O
as	O
"	O
feathers	O
"	O
in	O
Nightingale	B-Language
,	O
and	O
give	O
users	O
and	O
artists	O
the	O
ability	O
to	O
change	O
the	O
look	O
of	O
Nightingale	B-Language
via	O
an	O
extension	O
which	O
generates	O
a	O
default	O
skin	B-Application
.	O
</s>
<s>
Using	O
CSS	B-Language
(	O
and	O
optionally	O
XUL	B-Application
)	O
,	O
and	O
an	O
image	O
manipulation	O
program	O
such	O
as	O
Photoshop	B-Operating_System
or	O
GIMP	B-Application
,	O
users	O
are	O
then	O
able	O
to	O
make	O
Nightingale	B-Language
look	O
however	O
they	O
want	O
.	O
</s>
