<s>
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
(	O
often	O
abbreviated	O
TMP	O
)	O
was	O
a	O
Mozilla	B-Application
Firefox	I-Application
extension	B-Operating_System
that	O
adds	O
to	O
the	O
tabbed	O
browsing	O
functions	O
in	O
Firefox	B-Application
.	O
</s>
<s>
It	O
was	O
a	O
popular	O
extension	B-Operating_System
on	O
Mozilla	O
Add-ons	B-Operating_System
,	O
which	O
records	O
download	O
statistics	O
.	O
</s>
<s>
Lifehacker	O
named	O
it	O
one	O
of	O
their	O
"	O
Top	O
10	O
must-have	O
Firefox	B-Operating_System
extensions	I-Operating_System
"	O
for	O
2009	O
.	O
</s>
<s>
PC	O
World	O
said	O
that	O
"	O
With	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
,	O
Firefox	B-Application
tabs	O
go	O
past	O
the	O
obvious	O
and	O
into	O
the	O
indispensable	O
...	O
it	O
's	O
hard	O
to	O
imagine	O
how	O
you	O
lived	O
without	O
it.	O
"	O
</s>
<s>
As	O
the	O
only	O
extension	B-Operating_System
providing	O
multi-row	O
tab	O
support	O
,	O
Wired	O
and	O
CNET	O
both	O
called	O
it	O
a	O
"	O
must-have	O
"	O
that	O
is	O
"	O
powerful	O
"	O
and	O
"	O
gives	O
you	O
what	O
feels	O
like	O
an	O
infinite	O
amount	O
of	O
control	O
over	O
tab	O
behaviour.	O
"	O
</s>
<s>
The	O
original	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
ceased	O
to	O
be	O
compatible	O
with	O
Firefox	B-Application
upon	O
the	O
release	O
of	O
Firefox	B-Application
57	O
Quantum	O
,	O
due	O
to	O
the	O
switch	O
to	O
the	O
WebExtensions	B-Operating_System
interface	O
.	O
</s>
<s>
A	O
complete	O
rewrite	O
of	O
the	O
extension	B-Operating_System
under	O
development	O
build	O
has	O
been	O
released	O
,	O
called	O
Tab	O
Mix	O
WebExtension	B-Operating_System
,	O
with	O
limited	O
features	O
and	O
not	O
yet	O
compatible	O
with	O
Quantum	O
.	O
</s>
<s>
The	O
Add-Ons	B-Operating_System
functions	O
include	O
:	O
</s>
<s>
Allows	O
JavaScript	B-Language
to	O
be	O
forced	O
into	O
a	O
separate	O
tab	O
instead	O
of	O
a	O
pop-up	O
box	O
,	O
and	O
allows	O
the	O
user	O
to	O
view	O
the	O
URL	O
of	O
the	O
JavaScript	B-Language
page	O
.	O
</s>
<s>
While	O
Firefox	B-Application
contains	O
a	O
basic	O
session	O
manager	O
functions	O
,	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
has	O
greater	O
functionality	O
in	O
this	O
area	O
.	O
</s>
<s>
In	O
turn	O
,	O
the	O
Session	O
Manager	O
extension	B-Operating_System
has	O
additional	O
session	O
management	O
functions	O
beyond	O
those	O
of	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
.	O
</s>
<s>
These	O
two	O
extensions	O
are	O
known	O
to	O
"	O
play	O
nicely	O
together	O
"	O
:	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
detects	O
the	O
presence	O
of	O
Session	O
Manager	O
and	O
deactivates	O
its	O
own	O
session	O
management	O
functions	O
,	O
deferring	O
to	O
Session	O
Manager	O
.	O
</s>
<s>
Two	O
versions	O
of	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
are	O
generally	O
available	O
at	O
any	O
given	O
time	O
:	O
</s>
<s>
Intended	O
for	O
general	O
use	O
,	O
this	O
is	O
publicly	O
available	O
from	O
the	O
Mozilla	O
Add-ons	B-Operating_System
website	O
.	O
</s>
<s>
These	O
releases	O
have	O
passed	O
the	O
Mozilla	O
Add-ons	B-Operating_System
review	O
process	O
.	O
</s>
<s>
Versions	O
of	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
are	O
available	O
for	O
virtually	O
all	O
releases	O
of	O
Firefox	B-Application
prior	O
to	O
Firefox	B-Application
57	O
.	O
</s>
<s>
The	O
release	O
of	O
Firefox	B-Application
57	O
Quantum	O
marked	O
the	O
switchover	O
from	O
XUL-based	O
AddOns	B-Operating_System
—	O
which	O
allow	O
extensions	O
to	O
make	O
arbitrary	O
changes	O
to	O
Firefox	B-Application
code	O
—	O
to	O
the	O
WebExtensions	B-Operating_System
API	O
,	O
which	O
strictly	O
limits	O
how	O
much	O
control	O
extensions	O
have	O
over	O
the	O
browser	O
and	O
interface	O
.	O
</s>
<s>
Because	O
the	O
original	O
Tab	B-Operating_System
Mix	I-Operating_System
Plus	I-Operating_System
is	O
a	O
XUL-based	O
extension	B-Operating_System
,	O
it	O
does	O
not	O
work	O
with	O
Firefox	B-Application
57	O
or	O
higher	O
.	O
</s>
<s>
A	O
complete	O
rewrite	O
of	O
the	O
extension	B-Operating_System
,	O
called	O
Tab	O
Mix	O
WebExtension	B-Operating_System
,	O
is	O
in	O
progress	O
,	O
and	O
a	O
development	O
build	O
with	O
limited	O
functionality	O
has	O
been	O
released	O
.	O
</s>
