I get reports from users experiencing the error below in IE9 causing our (EmberJS) application to crash. I haven't found what's causing it yet because I'm unable to reproduce it through Browserstack or locally and I've got users in IE9 without problems (only a couple of users are affected).
Unable to get value of the property 'parentNode': object is null or undefined
Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET4.0C; .NET4.0E; InfoPath.3; MS-RTC LM 8)