This error only shows up in the legacy clients. It can be caused by a great number of things, that can often be very hard to track down.
Causes and Fixes
- Using the ToggleSearch() function on legacy clients.
- Test: Do any of the views utilize the ToggleSeach() function in a way that makes it execute on legacy clients?
- Fix: Only use ToggleSearch() in conjunction with IsHtml5() inside of a test(), such that ToggleSearch() will only run on html5 clients.