Cannot call method 'substr' of undefined error

I get this error here and there in my webpage but i can’t figure out when and why exactly. This happend at the load of the page. I tried with v2.0.1 and with the trunk version.

I will investigate further when i will have time.


  • Uncaught TypeError: Cannot call method ‘substr’ of undefined includes.js:165
  • toggleIt includes.js:165
  • toggleHidden includes.js:180
  • buttonShow includes.js:147
  • $.ajax.success includes.js:117
  • f.Callbacks.n jquery.1.7.1.js:2
  • f.Callbacks.o.fireWith jquery.1.7.1.js:2
  • w jquery.1.7.1.js:4
  • jquery.1.7.1.js:4

When it happen

  • For now, it only happen if MiniProfiler.Settings.PopupShowTrivial = true. Put it to false and the problem is gone!

  • The problem occur because there some html tags missing in the popup. The href tag with the class toggle-trivial is missing sometimes and i don’t know why.

Same problem here, running latest release. Cannot find exact cause.