[PySide] QWebEngineView resize error

[Dennis Pielken]

Dear all,


I want to use QWebEngineView to create a screenshot of a complete web 
page. This is mostly working for “shorter pages”, but it is not working 
for longer pages.

The only solution to take a screenshot of a complete webpage is to 
resize the QWebEngineView to the contentSize of QWebEnginePage. The 
following code is working for shorter pages (self inherits QWebEngineView):

     size = self.page().contentsSize().toSize()
     self.resize(size)
     QTimer.singleShot(2000, lambda: self.take_screenshot(size))

     def take_screenshot(self, size):

         img = QImage(size, QImage.Format_ARGB32)

         self.render(img)

         img.save(self.save_file)

The timer is only there to have enough time to resize the widget.

This code generates a full-web-page screenshot for most pages, such as 
slashdort.org. But when visiting https://thetechportal.com/ and 
scrolling down several times, so that additional content is loaded, the 
code line

     self.resize(size)

generates the following errors:

    QOpenGLFramebufferObject: Framebuffer incomplete attachment.

    QOpenGLFramebufferObject: Framebuffer incomplete attachment.

    QOpenGLFramebufferObject: Framebuffer incomplete attachment.

    QOpenGLFramebufferObject: Framebuffer incomplete attachment.

    QOpenGLFramebufferObject: Framebuffer incomplete, missing attachment.

    [13092:9676:0908/151509.277:ERROR:gles2_cmd_decoder.cc(5678)]
    GLES2DecoderImpl::ResizeOffscreenFramebuffer failed to allocate
    storage due to excessive dimensions.

    [13092:9676:0908/151509.278:ERROR:gles2_cmd_decoder.cc(5827)]
    GLES2DecoderImpl: Context lost because ResizeOffscreenFramebuffer
    failed.

    [13092:9676:0908/151509.278:ERROR:gles2_cmd_decoder.cc(5963)] Error:
    5 for Command kResizeCHROMIUM

This error can be reproduced with longer Facebook timelines as well.

The gles2 errors (the last three lines) are repeated indefinitely. I 
have not found a way to fix this. I have checked that the page is not 
bigger than the maximum size of the widget.

I am running Windows 10, Python 3.8.1, PySide2 5.14.2.3.

Is this a bug in PySide2 / Qt or how can I take a screenshot of a longer 
page? I have tried this example with PyQt as well and ran into the same 
errors…

Thanks for any help.

Best Regards

Dennis