Unresponsive Script?

I've been receiving the following error from Firefox more and more often over the past month:

As pictured, it usually happens when uploading photos to flickr, but it has happened with other sites. I'll be uploading, eventually this error comes up, I click on the "Stop Script" button, the error disappears, and everything continues as if nothing happened. Supposedly, this is a "helpful" message that results from pages that take "too long" to load.

After some poking around, I found the following solution on lifehacker.

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.
4. Bask in interruptionless browsing!