Firefox: How To Increase Default Javascript Execution Time

Firefox has the annoying habit of popping up an error message after 5 seconds (10 seconds for Firefox 2.x) when running Javascript code. This causes lots of irritation because a) some script genuinely need more than the default time, b) the error message pops up repeatedly after every 5-10 seconds thereby severely ruining your browsing experience and c) the strangely worded warning where Cancel is what allows you to continue responds very sluggishly and looks like hanging even on my Core 2 Duo machine. Fortunately there is a simple fix. With the current plethora of Web 2.0 applications I am sure you will need this sooner or later.

Type the following in your Firefox location bar (where you type in the url) and press Enter:
about:config

Now type the following in the Filter textbox:
dom.max_script_run_time

Now double-click on the line displaying - dom.max_script_run_time. Change the value to the number of seconds you want Firefox to wait before you get that message. I set mine to 120 (2 minutes). Just enter a number like 120.

Now close the about:config tab and then restart the browser. Henceforth the new settings will be effective.

Note: This is not an issue with Internet Explorer.