The customer in this case is me. You can catch all the gory technical details in my previous post.
The gist of the issue is that the popup blocker that is part of the Google Toolbar has a nasty way of silently defeating certain Internet Explorer functionality that may have absolutely nothing to do with popping up an annoying ad. The worst part about it is that Google Toolbar is otherwise a fine piece of software that does give you both visual and sound cues when it catches and stops popups.
This started two days ago when I discovered that part of functionality of our application ceased to work under Internet Explorer 6 and was data was being lost. I could easily reproduce the problem on a few machines in the office (all with IE6 and up to date on latest patches) but the problem did not appear on a virgin install of Windows 2000 with an older version if IE. After a day of getting nowhere in my testing and trying various changes to code, I contacted Microsoft Support and initiated a $245 support incident. Another day went by during which I exchanged a number of emails with the Microsoft tech until he suggested I check what Browser Helper Objects I had installed on my machine. It turned out I only had two: Acrobat Reader and Google Toolbar. A quick Google search (ironic, no?) revealed that in its early days Google's popup blocker was doing nothing more that disabling exactly the functionality I was now missing. Bingo!
To sum up, Google Toolbar disables the browser “onunload” event whenever the browser window is being closed. It does so indiscriminately of whether there is any code there that tries to launch a popup. Moreover, it does so without any indication to the user that it had altered the intended site experience. It cost me two days and $245 to track this down. Now, I have to figure out how to get around it. So far, Google Toolbar support has not responded to my email.
Just think the kind of furor would ensue if Microsoft were to do something like that? Guess what though, the MSN Toolbar's popup blocker manages to do its thing without such nasty side-effects. As does the Yahoo Toolbar.
For the record, as of this writing the Google Toolbar is at version 2.0.110-big/en (GGLD).