Information
This setting determines the amount of time, in seconds, which the system will wait before displaying the Software Update dialogue box (after an unobtrusive alert has already been shown).
Rationale:
Encouraging the user to update software as soon as possible mitigates the risk that a system will be left vulnerable.
Impact:
For this preference to have an effect app.update.enabled must be true.
Solution
To establish the recommended configuration, set app.update.promptWaitTime to 172800:
Type about:config in the address bar
Type app.update.promptWaitTime in the filter
Configure the setting as prescribed.
OR
Open the mozilla.cfg file in the installation directory with a text editor
Add the following lines to mozilla.cfg:
lockPref('app.update.promptWaitTime', 172800);
Default Value:
691200