Viewer window appears but remains empty/transparent

[fredex]

Running Calibre on Rocky Linux 9.3. Just upgraded Calibre from 7.06 to 7.10.

Now, when I try to view a book, either from the Calibre book listing, or by directly invoking the ebook reader, the reader starts, the window borders and header are drawn, the header shows the book title, but the window is never populated. it simply shows as a transparent window onto the desktop wallpaper. see attached image.

I tried reverting to a previous version, using the instructions on the Linux download page, but that failed. browsing to the directory given in that command, I don't see any of the recent releases there for download, only considerably older ones. Is there supposed to be a collection of recent versions there?

https://code.calibre-ebook.com/signatures/old/calibre-7.06.0-x86_64.txz.sha512

Thanks in advance for your assistance!

Fred

[fredex]

Oops. I said "pager window" but of course I mean "ebook viewer window".

[kovidgoyal]

You are probably using Wayland, switch back to X11.

And old releases of calibre are present at: https://download.calibre-ebook.com/

[BetterRed]

Originally Posted by fredex

Oops. I said "pager window" but of course I mean "ebook viewer window".

Fixed

[fredex]

Kovidgoyal:

from: https://unix.stackexchange.com/quest...-is-being-used

$ loginctl
SESSION  UID USER   SEAT  TTY STATE  IDLE SINCE
      2 1000 fredex seat0 n/a active no        

1 sessions listed.
[fredex@rockybox ~/Desktop]$ loginctl show-session 2  -p Type
Type=x11
[fredex@rockybox ~/Desktop]$

which indicates I am using X11, NOT Wayland.

I also checked almost all the other techniques in that posting and they all agree it is x11, not wayland.

Do you have any further thoughts on this problem?

Thanks for the correct URL for old releases.

[kovidgoyal]

You want to be sure you are running calibre under x11 run it as:


QT_QPA_PLATFORM=xcb calibre

[fredex]

Kovid:

Thanks for the further advice!

However:
starting calibre either with or without that prefix works fine, if all I do is work inside Calibre.
starting the ebook viewer from within Calibre (whether the prefix was used when starting Calibre, or not) still doesn't work.
starting the ebook viewer from the command line still does not work, regardless of whether the prefix was used, OR NOT.

running ebook-viewer like this:

$ strace --output=ebook-viewer-strace --output-separately /usr/bin/ebook-viewer
QGLXContext: Failed to create dummy context
QRhiGles2: Failed to create temporary context
QRhiGles2: Failed to create context
Failed to create QRhi for QBackingStoreRhiSupport
QRhiGles2: Failed to create temporary context
QRhiGles2: Failed to create context
Failed to create QRhi for QBackingStoreRhiSupport
QQuickWidget: Failed to get a QRhi from the top-level widget's window
QQuickWidget::resizeEvent() no QRhi
QRhiGles2: Failed to create temporary context
QRhiGles2: Failed to create context
Failed to create QRhi for QBackingStoreRhiSupport
QQuickWidget: Failed to get a QRhi from the top-level widget's window
QQuickWidget: Attempted to render scene with no rhi
QQuickWidget: Attempted to render scene with no rhi

gives the above output on the terminal.

the strace output from that same run is attached... Whoops, no it isn't. I keep getting "invalaid file" when trying to upload it. It is 4.1 MB, is that too big to attach?

Fred

[kovidgoyal]

Your GPU drivers are broken. Fix them or turn off hardware acceleration for qt webengine as described in

https://doc.qt.io/qt-6/qtwebengine-debugging.html

[fredex]

Thanks for the info!

During the interval between my last msg and yours I went back to 7.06.0, which had been working, and I had looked at the updates installed in recent days, and find that kmod-nvidia was updated on May 2. It is possible that I had not used the reader since then.

I MIGHT be able to downgrade to the previous version of that package, and will try it later when I get time (busy day today), and if all else f ails will look at your qt link.

Thanks!

Fred

[fredex]

Having a few mins, I looked at the URL you give above, and as a result tried entering at the commanline:

QTWEBENGINE_CHROMIUM_FLAGS="--disable-gpu" ebook-viewer

which, unfortunately made not a bit of difference.

[fredex]

Well, I've solved the problem (sorry for the late reply).

The next time I ran a system update the result was Calibre working correctly. So, there must have been some kind of out-of-sync between various system libraries.

Sorry 'bout all the whining!

Fred