Xpra: Ticket #1145: pixbuf backend does not support transparency with desktop scaling enabled

Most part of the terminal (using xfce4-terminal and terminator) appear black, mainly when the terminal has the focus. I just updated to ubuntu xenial and xpra 0.17.0 both on the client and on the server (server being a docker container) but the problem is still there. As display manager normally using i3 but the problem also occurs with the standard ubuntu display manager.

I have been experiencing the problem on different ubuntu and fedora versions on different machines including virtual box vms.

On the server side I run a docker container based on https://github.com/retog/docker-dev.



Tue, 15 Mar 2016 10:20:00 GMT - retog: attachment set


Tue, 15 Mar 2016 10:33:33 GMT - retog:

Just found that the problem does not occur when starting with --opengl=yes.

The Sesssion Info - Features shows

Client OpenGL (checked) Intel Open Source Technology Center /Mesa DRI Intel (R) HD graphics 520 (Skylake GT2)

Without the parameter (i.e. when the problem occurs):

Client OpenGL (unchecked) PyOpenGL version 3.1 or later is required (found version 3.0.2)


Tue, 15 Mar 2016 10:37:13 GMT - Antoine Martin:

It is probably transparency related, the cairo backend does not get as much testing. And there are issues with virtualbox too. PyOpenGL 3.1 has been out for years... so we're not going to support anything older than that.


Tue, 15 Mar 2016 11:48:43 GMT - retog:

As even the newest ubuntu distro comes with a too old PyOpenGL version the installation instructions should say how to get a compatible version.


Wed, 16 Mar 2016 03:54:38 GMT - Antoine Martin: status, summary, milestone changed

As even the newest ubuntu distro comes with a too old PyOpenGL version the installation instructions should say how to get a compatible version.


You should not be messing up with your system installed packages if you don't know how to do that and how to revert it later.

We should just make sure the non-opengl fallback works as it should. r12148 fixes that by disabling transparency for the non-opengl gtk pixbuf + cairo case, this will be backported to v0.16.x

I am keeping this ticket open because we should really support transparency with cairo, but not a huge priority.


Wed, 16 Mar 2016 07:15:55 GMT - retog:

You should not be messing up with your system installed packages

I did not! I installed xpra following exactly the instruction on unmodified ubuntu installations (including xenial).


Tue, 12 Jul 2016 16:52:22 GMT - Antoine Martin: milestone changed

Milestone renamed


Wed, 10 Aug 2016 03:36:06 GMT - Antoine Martin: status changed; resolution set

I did not! I installed xpra following exactly the instruction on unmodified ubuntu installations (including xenial).


I meant that if your distro supplies an outdated pyopengl, you should not try to install a newer one on top.

In any case, the non-opengl backends are legacy and therefore I am not going to spend time fixing the desktop-scaling + transparency + non-opengl combination. Especially since most distros will have opengl support in the next release, including outdated Debian + Ubuntu, see #1275.


Mon, 10 Jul 2017 06:36:11 GMT - Antoine Martin:

r16261 re-enables transparency with the pixmap backend since I am no longer seeing any visual corruption with desktop-scaling enabled. Even the cairo backend seems to paint transparency+scaling just fine (both in GTK3 #640 and with GTK2 and XPRA_USE_CAIRO_BACKING=1 env switch).

These changes are now tracked in #1570.


Mon, 10 Jul 2017 11:28:34 GMT - Antoine Martin: status changed; resolution deleted


Mon, 10 Jul 2017 11:29:40 GMT - Antoine Martin: status changed; resolution set

Tested OK on a number of different OS and backend combinations:

Works fine!


Sat, 23 Jan 2021 05:16:13 GMT - migration script:

this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/1145