I'm implementing a search service called SearchInsideOut. http://bit.ly/97SFyW This search service simply replaces web page results by full web pages (Yes, I used iframe). The problem I have to deal with is iframe-breaking pages. The promising solution I found is using onbeforeunload to let users decide whether to stay or leave my site. But this also creates another annoying behavior. When users click other links in my site, onbeforeunload will also be triggered. Fortunately, I could solve this case by placing window.onbeforeunload=null in the onclick event of those links of my site. Unfortunately, I have no idea how to detect external events like clicking "refresh/back" buttons. What should I do to solve this difficulty? All suggestions and comments are highly appreciated.