I have disabled the warning with "do not ask again" check box, now I want to get the warning again. How can I re-enable it?

  • 1
    Wait, so when I click "don't ask me again" and then press "Stop plugin", it doesn't just stop the plugin automatically without asking me? Grr ambiguous dialog boxes.
    – endolith
    May 16, 2013 at 19:10

3 Answers 3


Open the page about:config in a new tab, and reset the pref dom.max_script_run_time: http://kb.mozillazine.org/Dom.max_script_run_time


The "Don't ask me again" checkbox only applies to the currently running script.

If you haven't ticked it, the warning will pop up approximately every dom.max_script_run_time seconds while the script is still running.

Simply refresh the page (or run another script) and you should get the warning again if your script is taking too long.


Go to the about:config page.

In my Firefox there are now three script variables that are probably changed when checking the checkbox:


Just type script_run in the search box and it shows just these three. Right-click each one of them that's bold and choose 'Reset'.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .