When on https://commons.wikimedia.org/wiki/File:Commons_License_templates_usage_statistics_-_October_2016.pdf and clicking the preview's "Next page" link (which leads to https://commons.wikimedia.org/w/index.php?title=File:Commons_License_templates_usage_statistics_-_October_2016.pdf&page=2 ), I get an error notification on the top right stating:

https://commons.wikimedia.org/w/load.php?debug=false&lang=en&modules=ext.centralNotice.choiceData%2Cdisplay%2CgeoIP%2CkvStore%2CkvStoreMaintenance%2CstartUp%7Cext.centralauth.ForeignApi%7Cext.echo.api%2Cinit%7Cext.eventLogging%2CnavigationTiming%2CwikimediaEvents%7Cext.eventLogging.subscriber%7Cext.gadget.AjaxQuickDelete%2CCatScan2-link%2CCollapsibleTemplates%2CCropTool%2CDelReqHandler%2CGlamorous%2CGoogleImages%2CHotCat%2CImprovedUploadForm%2CLanguageSelect%2CLong-Image-Names-in-Categories%2CPermissionOTRS%2CQuickDelete%2CRenameLink%2CRotateLink%2CSlideshow%2CSum-it-up%2CTineye%2CUdelReqHandler%2CUploadWizard%2CWatchlistNotice%2CWikiMiniAtlas%2CZoomViewer%2Cadvanced-search%2Ccontribsrange%2Cfastcci%2ClibCommons%2ClibJQuery%2ClibUtil%2Crightsfilter%7Cext.gadget.jquery.blockUI%7Cext.uls.eventlogger%2Cinit%7Cext.visualEditor.targetLoader%7Cext.wikimediaEvents.loggedin%7Cjquery.checkboxShiftClick%2CgetAttrs%2ChighlightText%2CmakeCollapsible%2Cmw-jump%2Cplaceholder%2Cspinner%2Csuggestions%7Cmediawiki.ForeignApi%2Cfilewarning%2CsearchSuggest%2Cstorage%7Cmediawiki.ForeignApi.core%7Cmediawiki.action.view.metadata%7Cmediawiki.api.watch%7Cmediawiki.page.image.pagination%7Cmediawiki.page.ready%7Cmediawiki.page.watch.ajax%7Cmediawiki.ui.button%2Cicon%7Cmmv.bootstrap%7Cmmv.bootstrap.autostart%7Coojs%2Coojs-ui-core%2Csite%7Coojs-ui-core.styles%7Coojs-ui.styles.icons%2Cindicators%2Ctextures%7Cpdfhandler.messages%7Cschema.NavigationTiming%2CSaveTiming%2CUniversalLanguageSelector&skin=monobook&version=0lsrakz at line 197: TypeError: span.firstChild.getAttribute is not a function

Using Monobook and Firefox 49.0.1 on Windows 7 64-bit.