I love Firefox, the open-source web browser with a zillion and one little extensions and options. But there are maddening little quirks – like the way it turns uploading a largish file into an ordeal.

It’s something to do with the way Firefox handles scripts: impatiently. If something hasn’t happened for the last five seconds, Firefox alerts you with an “Unresponsive script” error, and asks you if you want to continue. Five seconds later, another dialog box. And another. And another, until the upload finally completes.

It turns out you don’t have to live with the heartbreak of Firefox’s short attention span. Instead, you can give it a quick dose of digital Ritalin with this handy, easy tip (from Lifehacker, by way of the Computer Vet blog):

  1. Type about:config in Firefox’s address bar.
  2. Filter down to the value for dom.max_script_run_time.
  3. Change the value to something higher than the default (which is 5.) I set mine to 20.

You do the filtering in step 2 by typing “dom.m” in the “Filter” bar that appears at the top of the page. Then double-click on the number that appears in the “Value” column. A dialog box pops up, where you enter your new numerical value; I used 100.

By the way, the dom.max_script_run_time value is the number of seconds Firefox should wait before asking “Are we there yet?” Bear in mind that you probably won’t be able to use Firefox at all while a script is running, so ask yourself how long you want to potentially be shut out of your browser.

If you want, you can set the value to 0, which Firefox takes to mean “Shut up and run the damn thing” – great if you don’t want to be interrupted, but maybe not so great if you run into some buggy Javascript.


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