How to open (externally opened) URLs in a new Chrome window in Mac OS X

Step 1. Save an application in Script Editor with the following content (JSX):

function GURLGURL(url) {
  const c = Application("Google Chrome");
  c.make({"new": "window"});
  c.activate();
  c.windows[0].activeTab.url = url;
}

Step 2. To prevent the application icon from showing up in Dock, edit the Info.plist of the application, adding:

<key>LSUIElement</key>
<true/>

Step 3. Re-save the application in Script Editor. (Make sure a new version is actually saved!)

Step 4. Select the application as the default web browser using the SwiftDefaultApps preference pane.