Click on Safari, then select Preferences.
Click on the Security tab.
Under Web Content, ensure that Enable plug-ins and Enable JavaScript are ticked.
Close the window.
Quit/exit Safari after you change settings and then re-start the application.
Click on Firefox and select Preferences.
Click on the Content tab.
Ensure that Enable JavaScript is ticked.
Close the window.
Quit/exit Mozilla Firefox after you change settings and then re-start the application.