Arch Linux

Maniaxx

Member

Registered: 2014-05-14

Posts: 738

QT5 windows are empty when opened from 'minimized' or 'systray'

When i close QT5 apps like 'qBittorrent' or 'Cadence' into systray or minimize and re-open them the window content is empty. The border is ok but the window body holds what's currently on the screen. If i re-size the window the body comes back properly.

There is nothing in 'Xorg.0.log', 'journalctl' or stderr. It started happening maybe a week ago.

Any idea what's wrong here?

Arch 5.1.14-arch1-1-ARCH
nouveau (kms), GTX770/NVE0
xfce (xfwm4 deactivated, no compositor)
x11/glamour
mesa 19.1.0-3
qt5-base 5.12.4-2

Last edited by Maniaxx (2019-06-25 23:00:29)

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sys2064

werkman2

Member

Registered: 2013-12-08

Posts: 14

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

i have the same with transmission-qt.
well, thats the only app that i have this problem with, im using kde plasma

Maniaxx

Member

Registered: 2014-05-14

Posts: 738

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

Sometimes qBittorrent crashes after some seconds.
'libQt5Widgets.so.5' is part of 'qt5-base' updated on 20-Jun-2019.
Looks like that's the culprit.

Stack trace of thread 24022:
#0  0x00007f496009666b n/a (libQt5Widgets.so.5)
#1  0x00007f496009a830 _ZN14QWidgetPrivate8moveRectERK5QRectii (libQt5Widgets.so.5)
#2  0x00007f49600bfc26 _ZN14QWidgetPrivate15setGeometry_sysEiiiib (libQt5Widgets.so.5)
#3  0x00007f49600c0784 _ZN7QWidget11setGeometryERK5QRect (libQt5Widgets.so.5)
#4  0x00007f4960238312 n/a (libQt5Widgets.so.5)
#5  0x00007f496023a706 n/a (libQt5Widgets.so.5)
#6  0x00007f49600c8b05 _ZN7QWidget5eventEP6QEvent (libQt5Widgets.so.5)
#7  0x00007f4960085485 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5)
#8  0x00007f496008e9b1 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5)
#9  0x000056334748f5c3 _ZN11Application6notifyEP7QObjectP6QEvent (qbittorrent)
#10 0x00007f495f3f7782 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5)
#11 0x00007f49600bf9b4 _ZN14QWidgetPrivate15setGeometry_sysEiiiib (libQt5Widgets.so.5)
#12 0x00007f49600c0784 _ZN7QWidget11setGeometryERK5QRect (libQt5Widgets.so.5)
#13 0x00007f4960238312 n/a (libQt5Widgets.so.5)
#14 0x00007f496023a706 n/a (libQt5Widgets.so.5)
#15 0x00007f49600c8b05 _ZN7QWidget5eventEP6QEvent (libQt5Widgets.so.5)
#16 0x00007f4960085485 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5)

Last edited by Maniaxx (2019-06-25 23:13:08)

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sys2064

kurt

Member

Registered: 2009-09-06

Posts: 140

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

Same problem with clementine-qt5-git

dmitry_k

Member

From: Russia

Registered: 2009-08-12

Posts: 10

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

Same problem here with qbittorrent, clementine and gnuplot.
I downgraded the entire qt5 group to version 5.12.3-1.
It seems to be working now.

If some of your applications depend on qt5-webkit package, which is not in gt5 group, it should also be downgraded to 5.212.0alpha2+156+g95401fe3908-1

phw

Member

Registered: 2013-05-27

Posts: 318

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

There seems to be some change how Qt handles widget lifetime when a window gets closed. I have seen this in an application I help to maintain also: Closing windows, but keeping the QWindow object around for later use, used to work. You could just show the window again. With Qt 5.12.4 it seems like the widgets get actually destroyed, so re-showing the window causes the content to be empty.

For the developers a workaround would be not to close, but to hide the window (which probably is also the more correct way to handle this). I could not find out whether this was an intentional change in Qt or not. It makes some sense to do it that way, but for existing applications this change of behavior is for sure unexpected.

Nocifer

Member

Registered: 2019-05-23

Posts: 14

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

I can confirm the above, you can easily verify it with e.g. qBittorrent, if you close it and then reopen it from the tray then initially only the title bar is visible; but if you move your mouse to where one of the clickable UI elements are supposed to be (e.g. the torrent control buttons in the main toolbar, the Transfers/Search/Log tabs at the top, or the General/Trackers/etc buttons at the bottom) and click it, then the window is repainted and once again becomes visible.

Has anyone reported this to the Qt bug tracker yet? Is this change in behavior officially documented somewhere? I couldn't find anything related with a quick search at their bug tracker but I currently don't have the time to properly report the bug myself. Also, just FYI there is no mention of this bug at the qBittorrent tracker as well, so it doesn't seem like the devs there are aware of the situation.

dmitry_k

Member

From: Russia

Registered: 2009-08-12

Posts: 10

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

Has anyone reported this to the Qt bug tracker yet?

Well, qt 5.12 branch is officially dead upstream, and qt 5.13 is now in Arch "testing".
It would be great, if someone could check this issue in Arch "testing".

Akhil701

Member

Registered: 2019-06-27

Posts: 1

Re: QT5 windows are empty when opened from 'minimized' or 'systray'

Can confirm it is resolved with qt 5.13 in Arch testing