show-compatibility-mode-warning.js

function checkCompatibilityMode(){
    var userAgentRegex = /MSIE ([0-9.]+)/;
    
    var userAgentData = userAgentRegex.exec(navigator.userAgent);
    
    if(userAgentData != null && typeof userAgentData[1] == "string"){
   	 //userAgentData[1] will hold the version number, e.g. "10.0"
   	 if(parseInt(userAgentData[1], 10) != document.documentMode){
   		 $('body').append('<div class="warning">Your browser appears to be in Compatibility Mode. This may cause problems when printing. <a href="http://www.howtogeek.com/128289/how-to-disable-compatibility-mode-in-internet-explorer/" target="_blank">Read how to turn off Compatibility Mode</a>.</div>');
   	 }
    }    
}