[1] [CITE@en[903332 – document.watch() results in "TypeError: can't watch non-native objects of class Proxy"]]
( ([TIME[2013-11-13 21:14:21 +09:00]] 版))
<https://bugzilla.mozilla.org/show_bug.cgi?id=903332>

[2] [CITE@en-US[Object.prototype.watch() - JavaScript | MDN]]
([TIME[2015-07-09 16:15:27 +09:00]] 版)
<https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/watch>

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[3] [CITE[An update on Object.observe]]
([TIME[2015-11-18 11:05:26 +09:00]] 版)
<https://esdiscuss.org/topic/an-update-on-object-observe>
]FIGCAPTION]

> >I agree with Benoit and I think there is a reason Object.prototype.watch is still in Firefox and won't go away any time soon
> As far as I know the only reason it's there and hasn't been removed is because it's used to implement debugger watchpoints '''['''1''']'''. And the only reason it's web-exposed is because SpiderMonkey has not prioritized being able to expose APIs to privileged code but not the web (something that think should get fixed).
> '''['''1''']''' bugzilla.mozilla.org/show_bug.cgi?id=934669

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