<s>
IAccessible2	B-Application
is	O
an	O
accessibility	O
API	B-General_Concept
for	O
Microsoft	B-Application
Windows	I-Application
applications	O
.	O
</s>
<s>
Initially	O
developed	O
by	O
IBM	O
under	O
the	O
codename	O
Project	O
Missouri	O
,	O
IAccessible2	B-Application
has	O
been	O
placed	O
under	O
the	O
aegis	O
of	O
the	O
Free	O
Standards	O
Group	O
,	O
now	O
part	O
of	O
the	B-Operating_System
Linux	I-Operating_System
Foundation	I-Operating_System
.	O
</s>
<s>
It	O
has	O
been	O
positioned	O
as	O
an	O
alternative	O
to	O
Microsoft	O
's	O
new	O
UI	B-Application
Automation	I-Application
API	B-General_Concept
.	O
</s>
<s>
While	O
UI	B-Application
Automation	I-Application
is	O
trumpeted	O
as	O
"	O
royalty-free	O
"	O
,	O
IAccessible2	B-Application
claims	O
to	O
be	O
an	O
"	O
open	O
standard	O
"	O
.	O
</s>
<s>
Whereas	O
UI	B-Application
Automation	I-Application
marks	O
a	O
radical	O
break	O
from	O
Microsoft	O
Active	O
Accessibility	O
(	O
MSAA	O
)	O
to	O
create	O
a	O
more	O
flexible	O
accessibility	O
API	B-General_Concept
,	O
IAccessible2	B-Application
fills	O
in	O
perceived	O
omissions	O
in	O
MSAA	O
to	O
match	O
the	O
Java	O
Accessibility	O
API	B-General_Concept
and	O
Assistive	B-Language
Technology	I-Language
Service	I-Language
Provider	I-Language
Interface	I-Language
(	O
AT-SPI	B-Language
)	O
.	O
</s>
<s>
By	O
extending	O
the	O
MSAA	O
interface	O
,	O
rather	O
than	O
replacing	O
it	O
,	O
IAccessible2	B-Application
allows	O
"	O
application	O
developers	O
to	O
leverage	O
their	O
investment	O
in	O
MSAA	O
while	O
also	O
providing	O
an	O
Assistive	O
Technology	O
(	O
AT	O
)	O
access	O
to	O
rich	O
document	O
applications.	O
"	O
</s>
<s>
Support	O
for	O
IAccessible	O
is	O
present	O
in	O
LibreOffice	B-Application
as	O
of	O
version	O
4.2	O
.	O
</s>
<s>
the	O
Opera	B-Application
web	I-Application
browser	I-Application
.	O
</s>
<s>
Although	O
IAccessible2	B-Application
was	O
introduced	O
as	O
a	O
Windows	O
accessibility	O
API	B-General_Concept
,	O
Qt	B-Language
Development	O
Frameworks	O
is	O
treating	O
IAccessible2	B-Application
as	O
a	O
potential	O
alternative	O
to	O
AT-SPI	B-Language
on	O
Linux	O
too	O
,	O
and	O
planning	O
to	O
add	O
preliminary	O
support	O
to	O
Qt	B-Language
4.3	O
.	O
</s>
<s>
As	O
of	O
2019	O
,	O
Qt	B-Language
uses	O
MSAA	O
and	O
IAccessible2	B-Application
on	O
Windows	O
,	O
and	O
continues	O
to	O
use	O
AT-SPI	B-Language
for	O
Unix/X11	O
systems	O
.	O
</s>
