Set opacity x-window-manager

I am working with a Colibri imx7d-emmc machine.
I have built a custom image based on tdx-reference-multimedia-image with x11-distro.
I have a X11 with one user application running on the system and I could auto run the app with
My app has QDialogs and when these dialogs are showed up the background should turn opaque, in older Yocto versions I archivied that enabling composite in x server and set a xml theme file as argument to the window manager, in that older version the system was using matchbox window manager.
I have not clear which window manager the system is using now. I know that the system is using an xserver-nodm service that execute xinit with /etc/X11/Xsession file. The Xsession file run scripts in /etc/X11/Xsession.d, one of this scripts is that run /usr/bin/x-window-manager. Finally, x-window.manager execute my app.
I have several questions about that:
There is an window manager runnning on the system? Which one?
There is a way to set this “opacity” theme?

Hi @emmaperea ,

Thanks for the detailed information!

Answering your questions:

There is a window manager runnning on the system? Which one?
The application runs directly on X, you can understand it better by checking the following recipes as an example:


The above files work together to initialize the application on X.

There is a way to set this “opacity” theme?
I searched a little and it seems that it is possible through some external tools, for more information please check this article. Some changes on recipe should be needed to enable the composites on X.

Please let me know if you have any more doubts.

Best regards,
Daniel Morais

Thank you @daniel_m.tx for the answer,
Yes I achivied to set opacity adding matchbox window manager.
Reading documentation I realized that the image wasn’t using a windows manager, so I added matchbox window manager and matchbox sato with a composite enabled and It works.