Whence the Javascript error “ReferenceError: Can't find variable: imenu_title”?

I recently added a window.onerror handler to a web application. The handler posts the details of the error — as much as the handler exposes — to my server, so I can see what kinds of errors users are seeing. The problem is that I’m seeing a lot of these:

ReferenceError: Can't find variable: imenu_title

or

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  • ReferenceError: Can't find variable: imenu_list_id
    

    The user agent for these is consistently an iPhone, for example:

    Mozilla/5.0 (iPhone; CPU iPhone OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Mobile/9B206
    

    I don’t have any code that uses those variables, and I’m suspicious that the errors are actually coming from some kind of extension installed on some user’s iPhone browser. Can anybody recognize these and point me in the right direction?

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  • One Solution collect form web for “Whence the Javascript error “ReferenceError: Can't find variable: imenu_title”?”

    That is unfortunately the breaks when using an onerror handler for the window object. I get more puzzling errors from javascirpt added by virus and link scanners, toolbars, and even some editions of certain browsers than I do actual page errors. And the comprehensible ones are most often caused by inline javascript (evil I know but quick for tests and replaced as quickly as possible with good code) that is activated before the library it uses is loaded or the pieces of the DOM it needs are loaded.

    No way to not have these errors happen, but they most likely will not effect how your page works in the browser. For more information about getting useful error reports, see https://stackoverflow.com/questions/8528005/are-there-any-tools-for-automatically-reporting-errors-from-client-side-javascri