When I pass the Qt application to the secondary monitor the characters of the application increase

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apport-collect 1824753

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Also, please try downgrading to mutter version 3.32.0-1 by downloading *.deb from:

  https://launchpad.net/ubuntu/+source/mutter/3.32.0-1/+build/16489975

and then install them with:

  dpkg -i *.deb

Now reboot and tell us if that fixes the problem.

apport information

apport information

I've updated Mutter as indicated. The problem is still there but it seems to have improved the resolution.
https://youtu.be/3-wFNodO8Qo

OK, if you have successfully downgraded mutter then it looks like this problem existed before the introduction of xrandr-scaling. So that's good. But just to verify, please run:

  dpkg -l | grep mutter

And send us the output.

patrick@patrick-pc:~$ dpkg -l | grep mutter
ii gir1.2-mutter-4:amd64 3.32.0+git20190410-1ubuntu1 amd64 GObject introspection data for Mutter
ii libmutter-4-0:amd64 3.32.0+git20190410-1ubuntu1 amd64 window manager library from the Mutter window manager
ii mutter 3.32.0-1 amd64 lightweight GTK+ window manager
ii mutter-common 3.32.0+git20190410-1ubuntu1 all shared files for the Mutter window manager
patrick@patrick-pc:~$

Thanks. It appears you have not downgraded all the packages, only one of them. Please repeat the steps in comment #2, being sure to download and install all the .deb files.

Now I do. Before I just updated mutter_3.32.0-1_amd64.deb.
I have updated all deb and the problem continues.

patrick@patrick-pc:~$ dpkg -l | grep mutter
ii gir1.2-mutter-4:amd64 3.32.0-1 amd64 GObject introspection data for Mutter
ii libmutter-4-0:amd64 3.32.0-1 amd64 window manager library from the Mutter window manager
iU libmutter-4-dev:amd64 3.32.0-1 amd64 Development files for the Mutter window manager
ii mutter 3.32.0-1 amd64 lightweight GTK+ window manager
ii mutter-common 3.32.0-1 all shared files for the Mutter window manager
patrick@patrick-pc:~$

Thanks. The problem continuing is somewhat good news. It means this isn't some new regression in mutter.

This bug talks about Qt applications and only gives vlc as example.

This bug is with all Qt applications. I used VLC to show it. And by the way, it happens with other distros that use GNOME 3.32.

> And by the way, it happens with other distros that use GNOME 3.32.

Thanks for the info! Do you know if this is caused by GNOME upgrade (3.30 -> 3.32) or by Qt upgrade (5.11 -> 5.12)?

Do you have any links to bugs in other distros or upstream?

I don't know if it's the GNOME 3.30 to 3.32 update or the Qt update. I know it happens with other distros because I tried Manjaro Gnome and it also suffers this bug. I left a message in the forums with another video https://forum.manjaro.org/t/gnome-two-monitors-and-qt-problems/83075

Thanks for the video! Can you please file a bug upstream to <https://bugreports.qt.io>?

My knowledge (of language and so on) is very basic, I am using a web translator. It is very difficult for me to advertise on the web <https://bugreports.qt.io>? If someone can or wants to do it I will be very grateful. I can provide as much information as required.
Thank you, greetings.

Status changed to 'Confirmed' because the bug affects multiple users.