: Help determining what is injecting broken code into my website On my website, I log client-side errors. Recently, a number of my users have been experiencing the following error: SyntaxError:

@Kaufman445

Posted in: #Error #GoogleAnalytics #Javascript

On my website, I log client-side errors. Recently, a number of my users have been experiencing the following error:

SyntaxError: Unexpected token var


and the "file" in which this occurs is:

data:application/javascript;base64,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


The interesting thing is that I don't use any base-64 encoded scripts at all. If you base64-decode and pretty-print the above blob, you get:

var urchinTracker = function() {},
_gaq = {
push: function() {
try {
if (arguments[0][0] == '_link') window.location.href = arguments[0][1]
} catch (er) {}
}
},
_gat = {
_createTracker: function() {},
_getTracker: function() {
return {
__noSuchMethod__: function() {},
_link: function(o) {
if (o) location.href = o;
},
_linkByPost: function() {
return true;
},
_getLinkerUrl: function(o) {
return o;
},
_trackEvent: function() {}
}
}
};
cxApi = {
setCookiePath: function() {},
chooseVariation: function() {}
}
var _gat = {
_getTrackerByName: function() {
_trackEvent: function() {}
}
};


This looks vaguely like Google Analytics code, and I do indeed use Google Analytics. But I also imagine that this is unlikely to be something Google Analytics is doing itself, because I generally expect Google products not to barf errors.

Has anyone seen this before / know what it is?

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