<s>
Encrypted	B-Language
Media	I-Language
Extensions	I-Language
(	O
EME	O
)	O
is	O
a	O
W3C	O
specification	O
for	O
providing	O
a	O
communication	O
channel	O
between	O
web	B-Application
browsers	I-Application
and	O
the	O
Content	O
Decryption	O
Module	O
(	O
CDM	O
)	O
software	O
which	O
implements	O
digital	O
rights	O
management	O
(	O
DRM	O
)	O
.	O
</s>
<s>
This	O
allows	O
the	O
use	O
of	O
HTML5	O
video	O
to	O
play	O
back	O
DRM-wrapped	O
content	O
such	O
as	O
streaming	B-Application
video	I-Application
services	O
without	O
the	O
use	O
of	O
heavy	O
third-party	O
media	O
plugins	O
like	O
Adobe	B-Operating_System
Flash	I-Operating_System
or	O
Microsoft	B-Application
Silverlight	I-Application
(	O
both	O
discontinued	O
)	O
.	O
</s>
<s>
EME	O
is	O
based	O
on	O
the	O
HTML5	O
Media	B-Language
Source	I-Language
Extensions	I-Language
(	O
MSE	O
)	O
specification	O
,	O
which	O
enables	O
adaptive	O
bitrate	O
streaming	O
in	O
HTML5	O
using	O
e.g.	O
</s>
<s>
MPEG-DASH	B-Protocol
with	O
MPEG-CENC	O
protected	O
content	O
.	O
</s>
<s>
EME	O
has	O
been	O
highly	O
controversial	O
because	O
it	O
places	O
a	O
necessarily	O
proprietary	B-Application
,	O
closed	O
decryption	O
component	O
which	O
requires	O
per-browser	O
licensing	O
fees	O
into	O
what	O
might	O
otherwise	O
be	O
an	O
entirely	O
open	O
and	O
free	O
software	O
ecosystem	O
.	O
</s>
<s>
In	O
April	O
2013	O
,	O
on	O
the	O
Samsung	B-Operating_System
Chromebook	I-Operating_System
,	O
Netflix	O
became	O
the	O
first	O
company	O
to	O
offer	O
HTML5	O
video	O
using	O
EME	O
.	O
</s>
<s>
,	O
the	O
Encrypted	B-Language
Media	I-Language
Extensions	I-Language
interface	O
has	O
been	O
implemented	O
in	O
the	B-Application
Google	I-Application
Chrome	B-Application
,	O
Internet	B-Application
Explorer	I-Application
,	O
Safari	B-Application
,	O
Firefox	B-Application
,	O
and	O
Microsoft	B-Application
Edge	I-Application
browsers	B-Application
.	O
</s>
<s>
While	O
backers	O
and	O
the	O
developers	O
of	O
the	O
Firefox	B-Application
web	I-Application
browser	I-Application
were	O
hesitant	O
in	O
implementing	O
the	O
protocol	O
for	O
ethical	O
reasons	O
due	O
to	O
its	O
dependency	O
on	O
proprietary	B-Application
code	O
,	O
Firefox	B-Application
introduced	O
EME	O
support	O
on	O
Windows	O
platforms	O
in	O
May	O
2015	O
,	O
originally	O
using	O
Adobe	O
's	O
Primetime	O
DRM	O
library	O
,	O
later	O
replaced	O
with	O
the	O
Widevine	O
library	O
(	O
CDM	O
)	O
.	O
</s>
<s>
Firefox	B-Application
's	O
implementation	O
of	O
EME	O
uses	O
an	O
open-source	B-Application
sandbox	O
to	O
load	O
the	O
proprietary	B-Application
DRM	O
modules	O
,	O
which	O
are	O
treated	O
as	O
plug-ins	B-Protocol
that	O
are	O
loaded	O
when	O
EME-encrypted	O
content	O
is	O
requested	O
.	O
</s>
<s>
The	O
sandbox	O
was	O
also	O
designed	O
to	O
frustrate	O
the	O
ability	O
for	O
services	O
and	O
the	O
DRM	O
to	O
uniquely	B-Protocol
track	I-Protocol
and	I-Protocol
identify	I-Protocol
devices	O
.	O
</s>
<s>
Additionally	O
,	O
it	O
is	O
always	O
possible	O
to	O
disable	O
DRM	O
in	O
Firefox	B-Application
,	O
which	O
then	O
not	O
only	O
disables	O
EME	O
,	O
but	O
also	O
uninstalls	O
the	O
Widevine	O
DRM	O
libraries	O
.	O
</s>
<s>
Netflix	O
supports	O
HTML5	O
video	O
using	O
EME	O
with	O
a	O
supported	O
web	B-Application
browser	I-Application
:	O
Chrome	B-Application
,	O
Firefox	B-Application
,	O
Microsoft	B-Application
Edge	I-Application
,	O
Internet	B-Application
Explorer	I-Application
(	O
on	O
Windows	O
8.1	O
or	O
newer	O
)	O
,	O
or	O
Safari	B-Application
(	O
on	O
OS	B-Device
X	I-Device
Yosemite	I-Device
or	O
newer	O
)	O
.	O
</s>
<s>
YouTube	B-General_Concept
supports	O
the	O
HTML5	O
MSE	O
.	O
</s>
<s>
Available	O
players	O
supporting	O
MPEG-DASH	B-Protocol
using	O
the	O
HTML5	O
MSE	O
and	O
EME	O
are	O
NexPlayer	O
,	O
THEOplayer	O
by	O
OpenTelly	O
,	O
the	O
bitdash	O
MPEG-DASH	B-Protocol
player	O
,	O
dash.js	O
by	O
DASH-IF	O
or	O
rx-player	O
.	O
</s>
<s>
Note	O
that	O
certainly	O
in	O
Firefox	B-Application
and	O
Chrome	B-Application
,	O
EME	O
does	O
not	O
work	O
unless	O
the	O
media	O
is	O
supplied	O
via	O
Media	B-Language
Source	I-Language
Extensions	I-Language
.	O
</s>
<s>
Version	O
4.3	O
and	O
subsequent	O
versions	O
of	O
Android	B-Application
support	O
EME	O
.	O
</s>
<s>
The	O
major	O
issues	O
for	O
criticism	O
are	O
implementation	O
issues	O
for	O
open-source	B-Application
browsers	B-Application
,	O
entry	O
barriers	O
for	O
new	O
browsers	B-Application
,	O
lack	O
of	O
interoperability	O
,	O
concerns	O
about	O
security	O
,	O
privacy	O
and	O
accessibility	O
,	O
and	O
possibility	O
of	O
legal	O
trouble	O
in	O
the	O
United	O
States	O
due	O
to	O
Chapter	O
12	O
of	O
the	O
DMCA	O
.	O
</s>
<s>
In	O
July	O
2020	O
,	O
Reddit	B-Application
started	O
using	O
a	O
fingerprinting	O
mechanism	O
that	O
involves	O
loading	O
every	O
DRM	O
module	O
that	O
browsers	B-Application
can	O
support	O
,	O
and	O
logs	O
what	O
ends	O
up	O
loading	O
as	O
part	O
of	O
the	O
data	O
collected	O
.	O
</s>
<s>
Users	O
noticed	O
this	O
when	O
Firefox	B-Application
began	O
alerting	O
them	O
that	O
Reddit	B-Application
"	O
required	O
"	O
them	O
to	O
load	O
DRM	O
software	O
to	O
play	O
media	O
,	O
although	O
none	O
of	O
the	O
media	O
on	O
the	O
page	O
actually	O
needed	O
it	O
.	O
</s>
<s>
None	O
of	O
the	O
widely	O
used	O
CDMs	O
is	O
being	O
licensed	O
to	O
independent	O
open-source	B-Application
browser	B-Application
providers	O
without	O
paying	O
a	O
per-browser	O
licensing	O
fee	O
(	O
particularly	O
to	O
Google	B-Application
–	O
for	O
their	O
Widevine	O
CDM	O
,	O
which	O
is	O
used	O
in	O
nearly	O
all	O
recently	O
developed	O
web	B-Application
browsers	I-Application
)	O
.	O
</s>
