I recently ran into a problem while uploading files through HTML forms in Firefox. When I uploaded a file the browser would wait for a very long time, then the "Unresponsive Script" message appeared. Clicking on Stop Script would get the page to load immediately, but Continue would take several tries before the result page would load.
After searching through Bugzilla I came to the conclusion that it's possible an extension is causing the problem. To test, I first created a new profile and tried uploading a file to my file upload test servlet. The response came back immediately, even though the file I was transferring was 4 MB.
Next, I switched back to my normal profile and began removing extensions one at a time and trying to upload a file. It finally worked correctly when I removed SessionSaver .2. To get my session management capabilities I was able to install Session Manager which appears to work perfectly.
