code: function manipulatePage(page) {
          if (DEBUG && !page.phantom) inspectArgs("manipulatePage: ", page);
  
          if (timer !== undefined) {
              clearTimeout(timer);
          }
  
          // Inject an external script file.
          if (option["javascript-file"]) {
              page.injectJs(option["javascript-file"]);
          }
  
          // Inject an in-line script from the command line.
          if (option["inject-script"]) {
              var injectScript = option["inject-script"];
              injectScript = (typeof injectScript === "function") ?
                  injectScript.toString() : `function() { ${injectScript} }`;
              page.evaluateJavaScript(injectScript);
          }
  
          if (option.waitcapturedelay) {
              setTimeout(function () { return page }, +option.waitcapturedelay);
          } else {
              return page;
          }
      }
docs: Inject JavaScript into the open page.