1.  In the address bar, type about:config and press Enter.

2.  Click "I'll be careful, I promise" if a warning message appears.

3.  In the search box, search for javascript.enabled

4.  Toggle the "javascript.enabled" preference (right-click and select "Toggle" or double-click the preference) to change the value from "false" to "true".

5.  Click on the "Reload current page" button of the web browser to refresh the page.