I fix the issue I had with editor removing a script by Editor.EnableStripScriptTags = false
The reason it did not worked originally the window was cached.

But I still have a problem with JavaScript not working on front end of the site.

I add a custom button which opens a window. There I display library of scripts. When user selects the script I’m using JavaScript IPI to copy script in the editor. All that is works well.
When user submit the record that script not working. Script still in the editor and when I view html source on front end of the site JavaScript is there but not working.
Script Example:

 

<script>

var mydate=new Date()
var year=mydate.getYear()
if (year < 1000)
year+=1900
var day=mydate.getDay()
var month=mydate.getMonth()
var daym=mydate.getDate()
if (daym<10)
daym="0"+daym
var dayarray=new Array("Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday")
var montharray=new Array("January","February","March","April","May","June","July","August","September","October","November","December")
document.write("<small><font color='000000' face='Arial'><b>"+dayarray[day]+", "+montharray[month]+" "+daym+", "+year+"</b></font></small>")

</script>