TypeError: Cannot read property 'exists' of undefined
Closed, InvalidPublicPRODUCTION ERROR
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Assigned To

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Authored By

	bwang
	Aug 5 2021, 3:39 PM

Description

Error

mwversion: undefined
single document: https://logstash.wikimedia.org/app/discover#/doc/logstash-*/logstash-2021.08.05?id=evPuFnsBQzT5HGEiD1-O

normalized_message

TypeError: Cannot read property 'exists' of undefined

exception.trace

at Message.exists  <anonymous>:355:432
at Message.toString  <anonymous>:354:1900
at Message.plain  <anonymous>:355:259
at updateTooltipOnElement  <anonymous>:345:474
at updateTooltip  <anonymous>:345:953
at HTMLAnchorElement.<anonymous>  <anonymous>:346:365
at Function.each  https://de.wikipedia.org/w/load.php?lang=de&modules=jquery&skin=vector&version=8v0mf:5:278
at jQuery.fn.init.each  https://de.wikipedia.org/w/load.php?lang=de&modules=jquery&skin=vector&version=8v0mf:3:93
at jQuery.fn.init.$.fn.updateTooltipAccessKeys  <anonymous>:346:349
at HTMLDocument.<anonymous>  <anonymous>:261:1

Impact

1,786 errors in past 12 hrs
At the time of this writing, most errors are coming from de.wikipedia.org

Notes

Related Objects

Mentioned Here: T262493: Strategy for avoiding or excluding client side errors from gadgets and user scripts

Event Timeline

bwang created this task.Aug 5 2021, 3:39 PM

Restricted Application added a subscriber: Aklapper. · View Herald TranscriptAug 5 2021, 3:39 PM

bwang updated the task description. (Show Details)Aug 5 2021, 3:42 PM

If you look closely, that error is coming from a single IP address.

The stack trace tells us an anonymous function is calling updateTooltipAccessKeys.

at jQuery.fn.init.$.fn.updateTooltipAccessKeys  <anonymous>:346:349
at HTMLDocument.<anonymous>  <anonymous>:261:1

Given one IP address is causing this, we can likely assume this is a user/site gadget or a browser extension, however there's no information in this error that enables us to debug it further. T262493 might give us a clue about whether it was a user or site gadget in future, and guide us in how to deal with this but right now there's nothing we can do about this and we shouldn't worry about it only impacts a single user.

There is a similar error which references initInterlanguageEntryPoint in UniversalLanguageSelector.

my guess is that the client is modifying mw.Message in some way e.g. mw.Message = function (){}; mw.msg('foo').exists() // throws error

at Message.exists  <anonymous>:355:432
at Message.toString  <anonymous>:354:1900
at Object.mw.msg  <anonymous>:356:422
at initInterlanguageEntryPoint  <anonymous>:47:806
at HTMLDocument.init  <anonymous>:52:422
at mightThrow  https://de.wikipedia.org/w/load.php?lang=de&modules=jquery&skin=vector&version=8v0mf:49:833
at process  https://de.wikipedia.org/w/load.php?lang=de&modules=jquery&skin=vector&version=8v0mf:50:498

TypeError: Cannot read property 'exists' of undefinedClosed, InvalidPublicPRODUCTION ERRORActions