Thread: Issue with Calibre Viewer
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Old 06-01-2020, 08:51 AM   #4
RbnJrg
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Posts: 1,797
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Join Date: Mar 2013
Location: Rosario - Santa Fe - Argentina
Device: Kindle 4 NT
Quote:
Originally Posted by kovidgoyal View Post
That's a video driver issue. Note that windows 7 is not supported with calibre 4 precisely for this issue. You can try various workrounds:

1) Update your video drivers
2) Turn off hardware acceleration https://doc.qt.io/qt-5/qtwebengine-debugging.html
3) Stay with calibre 3.48 till you are able to move off windows 7
Many thanks. My video drivers are updated and turn off hardware acceleration by setting the environment variable

QTWEBENGINE_CHROMIUM_FLAGS="--disable-gpu" calibre-viewer

seems not to have any effect. The curious thing is that when the Viewer is able to display an epub correctly, then all epubs can be displayed, even those ones that wasn't able to at a first moment. I don't know why some epubs are showed without issues and others didn't.
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