title: WebSerial API Device cannot open port on Ubuntu
body: <p>I have tried to use the WebSerial API on Ubuntu after it worked on Windows and ChromeOS.
  When I try to connect a device, i get this error: <code>DOMException: Failed to open serial port.</code>
  <a href="https://i.stack.imgur.com/9jBEW.png" rel="nofollow noreferrer">Error</a></p>
  <p>I have created a udev rule but it did not work.</p>
  <pre><code>SUBSYSTEM==&quot;tty&quot;, ATTR{idVendor}==&quot;0eb8&quot;, ATTR{idProduct}==&quot;f010&quot;, ATTRS{serial}==&quot;0000:00:14.0&quot;, SYMLINK+=&quot;ttyMettler0&quot;
  </code></pre>
  <p>The device info:</p>
  <pre><code>looking at device '/devices/pci0000:00/0000:00:14.0/usb1/1-6':
      KERNEL==&quot;1-6&quot;
      SUBSYSTEM==&quot;usb&quot;
      DRIVER==&quot;usb&quot;
      ATTR{idProduct}==&quot;f010&quot;
      ATTR{bNumConfigurations}==&quot;1&quot;
      ATTR{avoid_reset_quirk}==&quot;0&quot;
      ATTR{configuration}==&quot;&quot;
      ATTR{bNumInterfaces}==&quot; 2&quot;
      ATTR{ltm_capable}==&quot;no&quot;
      ATTR{quirks}==&quot;0x0&quot;
      ATTR{manufacturer}==&quot;METTLER TOLEDO&quot;
      ATTR{serial}==&quot;67022056LW&quot;
      ATTR{speed}==&quot;12&quot;
      ATTR{urbnum}==&quot;10&quot;
      ATTR{busnum}==&quot;1&quot;
      ATTR{tx_lanes}==&quot;1&quot;
      ATTR{bConfigurationValue}==&quot;1&quot;
      ATTR{devnum}==&quot;5&quot;
      ATTR{bDeviceSubClass}==&quot;00&quot;
      ATTR{bmAttributes}==&quot;c0&quot;
      ATTR{idVendor}==&quot;0eb8&quot;
      ATTR{version}==&quot; 1.10&quot;
      ATTR{authorized}==&quot;1&quot;
      ATTR{maxchild}==&quot;0&quot;
      ATTR{product}==&quot;BCA-222-60U-1301-120 &quot;
      ATTR{bcdDevice}==&quot;100f&quot;
      ATTR{bDeviceClass}==&quot;02&quot;
      ATTR{rx_lanes}==&quot;1&quot;
      ATTR{bMaxPacketSize0}==&quot;8&quot;
      ATTR{bMaxPower}==&quot;500mA&quot;
      ATTR{devpath}==&quot;6&quot;
      ATTR{removable}==&quot;removable&quot;
      ATTR{bDeviceProtocol}==&quot;00&quot;
  
    looking at parent device '/devices/pci0000:00/0000:00:14.0/usb1':
      KERNELS==&quot;usb1&quot;
      SUBSYSTEMS==&quot;usb&quot;
      DRIVERS==&quot;usb&quot;
      ATTRS{bMaxPower}==&quot;0mA&quot;
      ATTRS{version}==&quot; 2.00&quot;
      ATTRS{devpath}==&quot;0&quot;
      ATTRS{busnum}==&quot;1&quot;
      ATTRS{bConfigurationValue}==&quot;1&quot;
      ATTRS{removable}==&quot;unknown&quot;
      ATTRS{authorized_default}==&quot;1&quot;
      ATTRS{serial}==&quot;0000:00:14.0&quot;
     
  </code></pre>
  <p>Is my udev correct? Has anyone a similar problem?</p>