When I accessed
https://pt.wikipedia.org/w/index.php?title=Wikip%C3%A9dia:Esplanada/propostas&curid=61666&action=history&debug=1
today I got the followingusing Firefox 57.0 (64-bit), while logged in or unregistered, I always get the error:
```lang=json>TypeError: $.collapsibleTabs.getSettings(...) is undefined [Learn More] collapsibleTabs.js:114:29
{> handleResize/< https://pt.wikipedia.org/w/skins/Vector/collapsibleTabs.js:114:29
"errorMessage": "TypeError: $.collapsibleTabs.getSettings(...) is undefined",> each https://pt.wikipedia.org/w/load.php:362:10
"url": "> handleResize https://pt.wikipedia.org/w/load.php?debug=false&lang=pt&modules=ext.centralNotice.choiceData%2Cdisplay%2CgeoIP%2CkvStore%2CkvStoreMaintenance%2CstartUp%7Cext.centralauth.ForeignApi%7Cext.centralauth.centralautologin.clearcookie%7Cext.cx.campaigns.contributionsmenu%7Cext.cx.eventlogging%2Cmodel%7Cext.cx.widgets.callout%7Cext.echo.api%2Cinit%7Cext.eventLogging%2CnavigationTiming%2Cpopups%2Cthanks%2CwikimediaEvents%7Cext.eventLogging.subscriber%7Cext.popups.images%7Cext.thanks.revthank%7Cext.uls.common%2Ccompactlinks%2Ceventlogger%2Cinit%2Cinterface%2Cpreferences%2Cwebfonts%7Cext.visualEditor.desktopArticleTarget.init%7Cext.visualEditor.supportCheck%2CtargetLoader%2Ctrack%2Cve%7Cext.wikimediaEvents.loggedin%7Cjquery.accessKeyLabel%2CbyteLength%2CcheckboxShiftClick%2Cclient%2Cconfirmable%2Ccookie%2CgetAttrs%2Chidpi%2ChighlightText%2Cmw-jump%2Csuggestions%2CtabIndex%2CtextSelection%2Cthrottle-debounce%7Cjquery.uls.data%7Cmediawiki.ForeignApi%2CRegExp%2CTitle%2CUri%2Capi%2Ccheckboxtoggle%2Ccldr%2Ccookie%2Cexperiments%2CjqueryMsg%2Clanguage%2Cnotification%2Cnotify%2CsearchSuggest%2Cstorage%2Ctemplate%2Cuser%2Cutil%7Cmediawiki.ForeignApi.core%7Cmediawiki.action.history%7Cmediawiki.action.view.postEdit%7Cmediawiki.api.options%2Cuser%2Cwatch%7Cmediawiki.language.data%2Cinit%7Cmediawiki.libs.pluralruleparser%7Cmediawiki.page.ready%2Cstartup%7Cmediawiki.page.watch.ajax%7Cmediawiki.template.mustache%2Cregexp%7Cmediawiki.ui.button%2Cicon%7Cmmv.bootstrap%2Chead%7Cmmv.bootstrap.autostart%7Coojs%2Coojs-ui-core%2Coojs-ui-windows%2Csite%7Coojs-ui-core.styles%7Coojs-ui.styles.icons-alerts%2Cicons-content%2Cicons-interactions%2Cicons-movement%2Cindicators%2Ctextures%7Cschema.UniversalLanguageSelector%7Cskins.vector.js%7Cuser.defaults&skin=vector&version=07e6j7b",skins/Vector/collapsibleTabs.js:98:4
"lineNumber": 579,Clicking on the first link, it shows the line
"columnNumber": 963,https://github.com/wikimedia/mediawiki-skins-Vector/blob/8842f744ee49a69fce24d0b4e1116068f97755d3/collapsibleTabs.js#L114
On Chrome 62, it looks like this:
"errorObject": {}> collapsibleTabs.js?0c860:115 Uncaught TypeError: Cannot read property 'expandedWidth' of undefined
}> at jQuery.fn.init.<anonymous> (collapsibleTabs.js?0c860:115)
```> at Function.each (load.php?debug=true&lang=pt&modules=jquery%2Cmediawiki|mediawiki.legacy.wikibits&only=scripts&skin=vector&version=1b46sjy:362)
> at handleResize (collapsibleTabs.js?0c860:98)
I believe there is some race condition and/or some missing dependency in the code (see e.g. rMW61d650befc58d4c5c9d82b3b0585e65c75766e9c).
**See also**
* {T110568}