<s>
Mutter	O
is	O
a	O
window	B-Application
manager	I-Application
initially	O
designed	O
and	O
implemented	O
for	O
the	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
,	O
but	O
then	O
evolved	O
to	O
be	O
a	O
Wayland	O
compositor	O
.	O
</s>
<s>
It	O
became	O
the	O
default	O
window	B-Application
manager	I-Application
in	O
GNOME	B-Application
3	O
,	O
replacing	O
Metacity	B-Language
which	O
used	O
GTK	B-Application
for	O
rendering	O
.	O
</s>
<s>
Mutter	O
uses	O
a	O
graphics	B-Library
library	I-Library
called	O
Clutter	B-Language
giving	O
it	O
OpenGL	B-Application
capability	O
.	O
</s>
<s>
Mutter	O
is	O
a	O
portmanteau	O
of	O
Metacity	B-Language
and	O
Clutter	B-Language
.	O
</s>
<s>
Mutter	O
can	O
function	O
as	O
a	O
standalone	O
window	B-Application
manager	I-Application
for	O
GNOME-like	O
desktops	O
,	O
and	O
serves	O
as	O
the	O
primary	O
window	B-Application
manager	I-Application
for	O
the	O
GNOME	B-Language
Shell	I-Language
,	O
which	O
is	O
an	O
integral	O
part	O
of	O
GNOME	B-Application
3	O
.	O
</s>
<s>
Mutter	O
is	O
extensible	O
with	O
plug-ins	B-Application
,	O
and	O
supports	O
numerous	O
visual	O
effects	O
.	O
</s>
<s>
GNOME	B-Language
Shell	I-Language
is	O
written	O
as	O
a	O
plug-in	B-Application
to	O
Mutter	O
.	O
</s>
<s>
Support	O
for	O
HiDPI	B-Algorithm
was	O
added	O
to	O
version	O
3.13	O
of	O
Mutter	O
by	O
Adel	O
Gadllah	O
.	O
</s>
<s>
Muffin	O
is	O
a	O
fork	O
of	O
Mutter	O
by	O
the	O
Linux	B-Application
Mint	I-Application
team	I-Application
for	O
their	O
Cinnamon	B-Language
desktop	I-Language
environment	I-Language
.	O
</s>
<s>
Cinnamon	B-Language
's	O
shell	O
,	O
a	O
fork	O
of	O
GNOME	B-Language
Shell	I-Language
,	O
is	O
written	O
as	O
a	O
plugin	B-Application
for	O
Muffin	O
.	O
</s>
