Question: Internet explorer 11 (latest) crashes with the message "Internet Explorer has stopped working" when opening developer tools and and I have my site open.
Chrome, Edge doesn't give the problem.

All the functionality in my site works correctly.

This is only with my site (intranet site)

[![enter image description here](https://i.stack.imgur.com/tCOfY.png)](https://i.stack.imgur.com/tCOfY.png)

When I debug it I get

> 
> Unhandled exception at 0x5B514C32 (mshtml.dll) in iexplore.exe: 0xC00000FD: Stack overflow (parameters: 0x00000001, 0x06EC2FFC).
> 
> 
> 

How can I troubleshoot what in my site causes this behavior?

I have tried resetting Internet Explorer and disabling all add-ins but because the issue is not to do with other sites I can only think the issue is to do someone specific in the html/ javascript in my site.

Answer: 
I found the answer by removing blocks from the site until I could narrow down the problem code

In my page `head`

```
  <link rel="stylesheet" href="~/css/site.css" />

```

and commenting out the first line in that css

```
/*@import url('site.css');*/

```
Removing duplicate CSS from Child iFrame JSP worked for me. However I need that CSS and I removed it for Debugging only and after debugging I enabled it again

Edit:
I have fixed the issue, there was a font-awesome css which was already included in parent JSP and I had included it in child JSP as well. I removed it from child JSP and it worked.