Generally, it is caused by the following situations:
- img, iframe, and frame with src attribute which is blank or non found items.
- any request from non-secure (non https) source.
- any usage of ‘about:’ such as about:blank
Trouble shooting:
- examine any src attribute of img, iframe and frame carefully
Solution:
- change src attribute to ‘javascript:false;’ or a ‘blank.html’
Browsers which have this issue:
- IE 6 and below
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