JavaScript Timeouts In Firefox

I love using Firefox for my web-browsing needs. So many themes, so many extensions, it's wonderful. But one setting in particular has caused me some aggravation lately.

The behavior that annoys me, is when you have a labor-intensive JavaScript running. Every five seconds, Firefox will prompt you mentioning that the script is taking a long time to execute. It's Firefox's way to give you way out if the JavaScript has entered an infinite loop or similar. Very nice feature, being able to abort the running code without losing the entire browser. It's nice, but every five seconds is a bit much.

I only started to notice this after I installed the Bookmarks Synchronizer extension. It's a fantastic extension that lets you synchronize bookmarks between your computer and a server. Especially useful for sharing one set between multiple computers. However, it's very labor-intensive, and can sometimes take a while to execute. Rather annoying if you are prompted every five seconds.

Doing some digging about on Google, I found a setting that changes the length of time between promptings. It's an integer value that represents the number of seconds to wait.

Open up about:config and alter the value of dom.max_script_run_time. I've been using a value of 60, which means I'll get a message every minute and seems to work very well.


  • Mozilla Firefox


  • 9/8/2005 - Article published.