function docCommentSupport(lang, callback) {
      var tokenName = 'doc-comment'
      var grammar = Prism.languages[lang]
      if (!grammar) {
        return
      }
      var token = grammar[tokenName]
      if (!token) {
        // add doc comment: /** */
        var definition = {}
        definition[tokenName] = {
          pattern: /(^|[^\\])\/\*\*[^/][\s\S]*?(?:\*\/|$)/,
          lookbehind: true,
          alias: 'comment'
        }
        grammar = Prism.languages.insertBefore(lang, 'comment', definition)
        token = grammar[tokenName]
      }
      if (token instanceof RegExp) {
        // convert regex to object
        token = grammar[tokenName] = {
          pattern: token
        }
      }
      if (Array.isArray(token)) {
        for (var i = 0, l = token.length; i < l; i++) {
          if (token[i] instanceof RegExp) {
            token[i] = {
              pattern: token[i]
            }
          }
          callback(token[i])
        }
      } else {
        callback(token)
      }
    }
The languages for which JS templating will handle tagged template literals.

JS templating isn't active for only JavaScript but also related languages like TypeScript, JSX, and TSX.