This code is loading on mobile and throwing JavaScript errors

edit

On mobile breadcrumbEl doesn't exist, so the reference to breadcrumbEl.children throws an error. Please add a return statement where breadcrumbEl doesn't match anything. Thanks in advance! I can replicate this error on this page when loaded in mobile Jdlrobson (talk) 16:25, 15 February 2019 (UTC)Reply

/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:51 jQuery.Deferred exception: Cannot read property 'children' of null TypeError: Cannot read property 'children' of null
    at http://en.m.wiki.x.io/w/index.php?title=User:Enterprisey/up-one-lvl-kbd.js&action=raw&ctype=text/javascript:5:67
    at fire (http://en.m.wiki.x.io/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:45:915)
    at Object.fireWith [as resolveWith] (http://en.m.wiki.x.io/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:47:114)
    at Object.deferred.(anonymous function) [as resolve] (http://en.m.wiki.x.io/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:50:603)
    at <anonymous>:6:10
    at Object.enqueue (http://en.m.wiki.x.io/w/load.php?debug=false&lang=en-gb&modules=startup&only=scripts&skin=minerva&target=mobile:12:508)
    at Object.mw.loader.using (<anonymous>:5:963)
    at HTMLDocument.<anonymous> (http://en.m.wiki.x.io/w/index.php?title=User:Enterprisey/up-one-lvl-kbd.js&action=raw&ctype=text/javascript:4:19)
    at mightThrow (http://en.m.wiki.x.io/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:48:856)
    at process (http://en.m.wiki.x.io/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:49:516) undefined
jQuery.Deferred.exceptionHook @ /w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:51
/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:51 Uncaught TypeError: Cannot read property 'children' of null
    at /w/index.php?title=User:Enterprisey/up-one-lvl-kbd.js&action=raw&ctype=text/javascript:5
    at fire (/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:45)
    at Object.fireWith [as resolveWith] (/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:47)
    at Object.deferred.(anonymous function) [as resolve] (http://en.m.wiki.x.io/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:50:603)
    at <anonymous>:6:10
    at Object.enqueue (/w/load.php?debug=false&lang=en-gb&modules=startup&only=scripts&skin=minerva&target=mobile:12)
    at Object.mw.loader.using (<anonymous>:5:963)
    at HTMLDocument.<anonymous> (/w/index.php?title=User:Enterprisey/up-one-lvl-kbd.js&action=raw&ctype=text/javascript:4)
    at mightThrow (/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:48)
    at process (/w/load.php?debug=false&lang=en-gb&modules=jquery&skin=minerva&version=0hjaxwj:49)
  Done Enterprisey (talk!) 23:35, 22 February 2019 (UTC)Reply