After testing, the following conclusions are drawn:
I think that when IE press F12, the development tool itself opens the error that is triggered when accessing certain resources, and does not have anything to do with the site.
According to my guess:
That is, the development tool accesses certain resources, and this access is accessed using JS, and this access also adheres to the access review process applied to certain websites, and this development tool has no special power over this audit process, and finally triggers the error prompt;
Conclusion the source repro step (domain name preparation can be modified by window's hosts to achieve)
1. URL: Prepare the domain name, http://l.com/, and the domain name http://l.com/index.html this file to place the following content:
<! DOCTYPE html>
<body>
<iframe src= "http://l2.com/l2.html" ></iframe>
<iframe src= "http://l2.com/l2.html" ></iframe>
<iframe src= "http://l2.com/l2.html" ></iframe>
</body>
2. Prepare the domain name http://l2.com/, the http://l2.com/l2.html under this domain name to place the following content
Abc
3, IE in no open state, using IE open http://l.com/index.html, press F12 Open Development tools, you can see the error prompt, if the http://l2.com/l2.html domain name access is a bit slow, you will find that only loading completed HTTP ://l2.com/l2.html After this error is prompted;
4. Close the development tool again, then open the development tool, then refresh the page and see the error again, then this hint will be the reason why
5. If the Http://l.com/index.html page is opened by another page, such as by <a href= "http://l.com/index.html" >aaaa</a> so click to open; Its error message would be to deny access:
Thus, this error is a development tool error is not a website error
The developer tool for IE is a JS error prompt that is triggered by opening the development tool when the page contains an IFRAME and the SRC domain is different.
