Legally avoiding popup blocking
<p>What is causing some browsers to see my code as unsolicited?</p>

<p>I have a web site devoted to helping people with interactive sessions. It starts with the user clicking [Begin] so this is a consented action. This should (1) open a popup while (2) redirecting the first page to a end page as below : </p>

<pre><code>&lt;head&gt;  
&lt;SCRIPT language="JavaScript"&gt;
      function openwindow(){window.open("{INTERACTION}","interaction","resizable=0,width=800,height=600,status=0");}&lt;/SCRIPT&gt;
&lt;/head&gt;   
&lt;body&gt;
&lt;FORM action="end.php" method="{METHOD}" &gt;  
&lt;input type="submit"  class="button" 
       onClick="javascript: openwindow()" 
       value="Begin" /&gt;
&lt;/FORM&gt;
&lt;/body&gt;
</code></pre>

<p>As said, this is not trying to open an unrequested popup but some strains of IE and Chrome appear to be treating it as such. I have been trying to get a fix, most recently digesting <a href="http://stackoverflow.com/questions/668286/detect-blocked-popup-in-chrome">this post</a>. </p>

<p>In it Bobince comments </p>

<blockquote>
  <p>these days, you don't really need to ask the question “was my unsolicited popup blocked?”, because the answer is invariably “yes” — all the major browsers have the popup blocker turned on by default. Best approach is only ever to window.open() in response to a direct click, which is almost always allowed.I'm quite happy to buy into this principle because I simply want my popup to open. </p>
</blockquote>

<p>What is causing some browsers to see my code as unsolicited?</p>

<p>I'd appreciate any help you could give me. (as you might have guessed, client side is not my bag and this topic has been bugging me for ages).</p>

<p>Many thanks in advance (and fingers crossed)
Giles</p>
