Tor: Should I disable JavaScript in Tor Browser?

Short answer

JavaScript is enabled in the Standard security level because many sites require it. If your risk calls for less active web content, choose Safer or Safest in Tor Browser's security settings; Safest disables JavaScript by default. Expect some sites to lose features. Changing NoScript rules for individual sites can weaken the benefit, so avoid exceptions you do not understand.

Sources

Tor Project: Security levels, Tor Project: Browser extensions.