You have been subscribed to a public bug:

We're running into a weird bug on Ubuntu : WebUSB works on Chrome but
doesn't on Chromium!

Here's our udev rule:

It uses the uaccess tag which adds an ACL to the created file in /dev/
so that the current logged-in user has RW access to the corresponding
/dev/bus/usb/** device. Apparently that's the way to go, since relying
on groups is fragile (not all distros use the "plugdev" group for

That udev rules works just fine. When using a command-line utility such
as "dfu-tool", the USB device is seen and can be read from and written
to. It also works just fine on Chrome. But Chromium gives us an "access
denied" error. It lists the device, we do get the pop-up, but we cannot
communicate. On Chromium, chrome://device-log says :

Failed to open /dev/bus/usb/001/011: Operation not permitted (1)

Here are the infos on said file:

user@virtualbox:~$ ls -l /dev/bus/usb/001/011
crw-rw-r--+ 1 root root 189, 10 Jul  3 11:35 /dev/bus/usb/001/011

As you can see, the file is owned root/root, but has an ACL (as shown by
the "+" symbol)

user@virtualbox:~$ getfacl /dev/bus/usb/001/011
getfacl: Removing leading '/' from absolute path names
# file: dev/bus/usb/001/011
# owner: root
# group: root

Here the ACL supposedely gives RW access to "user" who is indeed the
current logged-in user, and the user running Chromium and Chrome.

For reference :
 - Latest stable Ubuntu (18.04)
 - Using the Chromium that ships with Ubuntu (from the Ubuntu Software app. 
attached chrome://version page)
 - And using latest stable Chrome from (attached chrome://version 

** Affects: chromium-browser (Ubuntu)
     Importance: Undecided
         Status: New

Chromium cannot use WebUSB
You received this bug notification because you are a member of Desktop 
Packages, which is subscribed to chromium-browser in Ubuntu.

Mailing list:
Post to     :
Unsubscribe :
More help   :

Reply via email to